U.S. patent application number 14/542429 was filed with the patent office on 2015-06-18 for endoscopic device with double-helical lumen design.
This patent application is currently assigned to Auris Surgical Robotics, Inc.. The applicant listed for this patent is Auris Surgical Robotics, Inc.. Invention is credited to Joseph Bogusky, Enrique Romo.
Application Number | 20150164596 14/542429 |
Document ID | / |
Family ID | 52993670 |
Filed Date | 2015-06-18 |
United States Patent
Application |
20150164596 |
Kind Code |
A1 |
Romo; Enrique ; et
al. |
June 18, 2015 |
ENDOSCOPIC DEVICE WITH DOUBLE-HELICAL LUMEN DESIGN
Abstract
An endolumenal robotic system provides the surgeon with the
ability to drive a robotically-driven endoscopic device to a
desired anatomical position in a patient without the need for
awkward motions and positions, while also enjoying improved image
quality from a digital camera mounted on the endoscopic device.
Inventors: |
Romo; Enrique; (Dublin,
CA) ; Bogusky; Joseph; (San Jose, CA) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Auris Surgical Robotics, Inc. |
Redwood City |
CA |
US |
|
|
Assignee: |
Auris Surgical Robotics,
Inc.
Redwood City
CA
|
Family ID: |
52993670 |
Appl. No.: |
14/542429 |
Filed: |
November 14, 2014 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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14523760 |
Oct 24, 2014 |
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14542429 |
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61895312 |
Oct 24, 2013 |
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61895315 |
Oct 24, 2013 |
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61895602 |
Oct 25, 2013 |
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61940180 |
Feb 14, 2014 |
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62019816 |
Jul 1, 2014 |
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62037520 |
Aug 14, 2014 |
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Current U.S.
Class: |
604/104 ;
604/95.04 |
Current CPC
Class: |
A61B 2034/306 20160201;
A61B 2034/2048 20160201; A61B 1/0016 20130101; A61B 1/018 20130101;
A61B 1/00071 20130101; A61B 2034/301 20160201; A61M 25/0009
20130101; A61B 1/00149 20130101; A61B 2017/00477 20130101; A61B
34/30 20160201; A61M 25/0012 20130101; A61B 2034/742 20160201; A61B
1/0057 20130101; A61B 2034/2051 20160201; A61B 34/71 20160201; A61B
2017/00526 20130101; Y10T 29/49815 20150115; G16H 40/63 20180101;
A61B 34/37 20160201; A61B 1/00045 20130101; A61B 1/05 20130101;
A61B 90/30 20160201; A61B 90/361 20160201 |
International
Class: |
A61B 19/00 20060101
A61B019/00; A61B 1/00 20060101 A61B001/00; A61B 1/018 20060101
A61B001/018 |
Claims
1. An endoscopic instrument, comprising: a first elongated body
comprising a first lumen spiraled at a first angle along the length
of the first elongated body; a cavity along the length of the first
elongated body; a second elongated body comprising a second lumen
spiraled at a second angle along the length of the second elongated
body; wherein the second elongated body is positioned inside the
cavity of the first elongated body.
2. The instrument of claim 1, wherein the first angle varies along
the length of the first elongated body and the second angle varies
along the length of the second elongated body.
3. The instrument of claim 1, wherein the first angle and the
second angle are pre-selected.
4. The instrument of claim 1, wherein the second elongated body is
configured to slidingly move within the cavity of the first
elongated body.
5. The instrument of claim 1, further comprising: a first actuating
element that is positioned within the first lumen; and a second
actuating element that is positioned within the second lumen.
6. The instrument of claim 5, wherein the first angle is configured
to selectively distribute a first reactive force along the first
elongated body arising from application of a first actuating force
on the first actuating element; and the second angle is configured
to selectively distribute a second reactive force along the second
elongated body arising from application of a second actuating force
on the second actuating element.
7. The instrument of claim 6, wherein the first actuating element
is attached near the distal end of the first elongated body, such
that the application of the first actuating force on the first
actuating element results in the first reactive force along the
first elongated body; and the second actuating element is attached
near the distal end of the second elongated body, such that the
application of the second actuating force on the second actuating
element results in the second reactive force along the second
elongated body.
8. The instrument of claim 7, wherein the first reactive force
along the first elongated body does not affect the second reactive
in the second elongated body; and the second reactive force along
the second elongated body does not affect the first reactive force
in the first elongated body.
9. The instrument of claim 7, wherein the first actuating force and
the second actuating force may be applied independently of each
other.
10. The instrument of claim 1, wherein the second elongated body
further comprises a working channel that runs along the length of
the second elongated body.
11. The instrument of claim 10, wherein the working channel is
configured to convey a variety of tools down to the distal end of
the second elongated body.
12. The instrument of claim 1, further comprising an imaging means
at the distal end of the second elongated body.
13. The instrument of claim 12, further comprising an illumination
means configured to be used in conjunction with the imaging
means.
14. A method of performing a robotically-driven endoscopic
procedure comprising: providing an elongated instrument that
comprises: a first elongated body comprising a first lumen spiraled
at a first angle along the length of the first elongated body; a
cavity along the length of the first elongated body; a second
elongated body comprising a second lumen spiraled at a second angle
along the length of the second elongated body; wherein the second
elongated body is positioned inside the cavity of the first
elongated body; inserting the instrument into a patient; and
actuating the instrument with at least one degree of freedom to
control disposition of the distal end of the second elongated
body.
15. The method of claim 14, wherein the first angle varies along
the length of the first elongated body, and the second angle varies
along the length of the second elongated body.
16. The method of claim 14, wherein the second elongated body
further comprises a working channel.
17. The method of claim 14, wherein the first elongated body
further comprises a first actuating element that is positioned
within the first lumen; and the second elongated body further
comprises a second actuating element that is positioned within the
second lumen.
18. The instrument of claim 14, wherein the first angle is
configured to selectively distribute a first reactive force along
the first elongated body arising from application of a first
actuating force on the first actuating element; and the second
angle is configured to selectively distribute a second reactive
force along the second elongated body arising from application of a
second actuating force on the second actuating element.
19. The instrument of claim 18, wherein the first actuating element
is attached near the distal end of the first elongated body, such
that the application of the first actuating force on the first
actuating element results in the first reactive force along the
first elongated body; and the second actuating element is attached
near the distal end of the second elongated body, such that the
application of the second actuating force on the second actuating
element results in the second reactive force along the second
elongated body.
20. The method of claim 19, wherein actuating the instrument
involves applying the first actuating force to the first actuating
element or applying the second actuating force to the second
actuating element.
Description
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application is a continuation of U.S. patent
application Ser. No. 14/523,760 (Attorney Docket No.
41663-712.201), filed Oct. 24, 2014, which claims priority to U.S.
Provisional Patent Application No. 61/895,312, (Attorney Docket No.
41663-711.101), filed Oct. 24, 2013; U.S. Provisional Patent
Application No. 61/895,315, (Attorney Docket No. 41663-712.101),
filed Oct. 24, 2013; U.S. Provisional Patent Application No.
61/895,602, (Attorney Docket No. 41663-713.101), filed Oct. 25,
2013; U.S. Provisional Patent Application No. 61/940,180, (Attorney
Docket No. 41663-714.101), filed Feb. 14, 2014; U.S. Provisional
Patent Application No. 62/019,816, (Attorney Docket No.
41663-713.102), filed Jul. 1, 2014; and U.S. Provisional Patent
Application No. 62/037,520, (Attorney Docket No. 41663-715.101),
filed Aug. 14, 2014; the entire contents of which are incorporated
herein by reference.
[0002] This application is filed on the same day as and claims a
common chain of priority as the following applications: U.S. patent
application Ser. No. ______ (Attorney Docket No. 41663-712.301);
U.S. patent application Ser. No. ______ (Attorney Docket No.
41663-712.302); and U.S. patent application Ser. No. ______
(Attorney Docket No. 41663-712.303).
BACKGROUND OF THE INVENTION
[0003] 1. Field of the Invention
[0004] The field of the present application pertains to medical
devices. More particularly, the field of the invention pertains to
systems and tools for robotic-assisted endolumenal surgery.
[0005] 2. Description of the Related Art
[0006] Endoscopy is a widely-used, minimally invasive technique for
both imaging and delivering therapeutics to anatomical locations
within the human body. Typically a flexible endoscope is used to
deliver tools to an operative site inside the body--e.g., through
small incisions or a natural orifice in the body (nasal, anal,
vaginal, urinary, throat, etc.)--where a procedure is performed.
Endoscopes may have imaging, lighting and steering capabilities at
the distal end of a flexible shaft enabling navigation of
non-linear lumens or pathways.
[0007] To assist with the navigation, the endoscopes often have a
means to articulate a small distal bending section. Today's
endoscopic devices are typically hand held devices with numerous
levers, dials, and buttons for various functionalities, but offer
limited performance in terms of articulation. For control,
physicians control the position and progress of the endoscope by
manipulating the leavers or dials in concert with twisting the
shaft of the scope. These techniques require the physician to
contort their hands and arms when using the device to deliver the
scope to the desired position. The resulting arm motions and
positions are awkward for physicians; maintaining those positions
can also be physically taxing. Thus, manual actuation of bending
sections is often constrained by low actuation force and poor
ergonomics.
[0008] There are additional challenges with today's endoscopic
devices. Today's endoscopes typically require support personnel to
both deliver, operate and remove operative, diagnostic or
therapeutic devices from the scope while the physician maintains
the desired position. Today's endoscopes utilize pull wires that
create issues with curve alignment and muscling. Some procedures
require fluoroscopy or segmented CT scans to assist in navigating
to the desired location, particularly for small lumen
navigation.
[0009] Therefore, it would be beneficial to have a system and tools
for endolumenal procedures that provide improved ergonomics,
usability, and navigation.
SUMMARY OF THE INVENTION
[0010] In one aspect, the present invention provides for a system
performing robotically-assisted surgical procedures that comprises
a first robotic arm with a proximal end and a distal section, a
first mechanism changer interface coupled to the distal section of
the first robotic arm, a first instrument device manipulator
coupled to the first mechanism changer interface, the first
instrument device manipulator being configured to operate
robotically-driven tools that are configured to perform surgical
procedures at an operative site in a patient, and wherein the first
instrument device manipulator comprises a drive unit.
[0011] In related devices, the drive unit comprises a motor. In
some embodiments, the first instrument device manipulator is
configured to be releasably disengaged from the mechanism changer
interface and the first robotic arm.
[0012] In related devices, the first mechanism changer interface is
configured to interface with a plurality of instrument device
manipulators. In some embodiments, first mechanism changer
interface is configured to convey electrical signals from the first
robotic arm to the first instrument device manipulator.
[0013] In related devices, the present invention further comprises
an endoscopic tool coupled to the first instrument device
manipulator, the endoscopic tool comprising a primary elongated
body. In some embodiments, an electromagnetic tracker is coupled to
the distal section of the primary elongated body. In some
embodiments, an accelerometer is coupled to the distal section of
the primary elongated body.
[0014] In related devices, the primary elongated body comprises a
working channel longitudinally aligned with a neutral axis of the
primary elongated body, and a pull lumen aligned at an angle in a
helix around the working channel. In some embodiments, the angle of
the helix varies along the length of the primary elongated body. In
some embodiments, the pull lumen contains an elongated tendon
fixedly coupled to the distal section of the primary elongated body
and responsive to the first instrument device manipulator.
[0015] In related devices, the endoscopic tool further comprises a
secondary elongated body that is longitudinally aligned around the
primary elongated body, wherein the primary elongated body
comprises a proximal section and a distal section, and wherein a
digital camera is coupled to the distal end. In some embodiments,
the system further comprises a second robotic arm coupled to a
second instrument device manipulator through a second mechanism
changer interface, wherein the second instrument device manipulator
is coupled to the endoscopic tool, and the first instrument device
manipulator and the second instrument device manipulator are
configured to align to form a virtual rail to operate the
endoscopic tool. In some embodiments, the first instrument device
manipulator operatively controls the secondary elongated body and
the second instrument device manipulator operatively controls the
primary elongated body. In some embodiments, the first robotic arm
and the second robotic arm are coupled to a movable system cart. In
some embodiments, the first robotic arm and the second robotic arm
are coupled to an operating bed that is configured to hold the
patient. In some embodiments, the system cart is configured to send
sensor data to a command console and receive command signals from
the command console. In some embodiments, the command console is
separate from the system cart. In some embodiments, the command
console comprises a display module and a control module for
controlling the endoscopic tool. In some embodiments, the control
module is a joystick controller.
BRIEF DESCRIPTION OF THE DRAWINGS
[0016] The invention will be described, by way of example, and with
reference to the accompanying diagrammatic drawings, in which:
[0017] FIG. 1 illustrates a robotic endoscopic system, in
accordance with an embodiment of the present invention;
[0018] FIG. 2A illustrates a robotic surgery system in accordance
with an embodiment of the present invention;
[0019] FIG. 2B illustrates an overhead view of system 200 where
anesthesia cart 201 is provided towards the head of the
patient;
[0020] FIG. 2C shows an a view of system 200 in FIG. 2A;
[0021] FIGS. 2D and 2E illustrate alternative arrangements of arms
202 and 204 showing the versatility of the robotic surgical system
in accordance with embodiments of the present invention;
[0022] FIG. 3A illustrates an overhead view of a system with
multiple virtual rails, in accordance with an embodiment of the
present invention;
[0023] FIG. 3B illustrates the use of robotic surgery system from
FIG. 3A with an additional robotic arm, associated tool base, and
tool;
[0024] FIG. 4 illustrates a robotic surgery system with
interchangeable IDMs and tools, in accordance with an embodiment of
the present invention;
[0025] FIG. 5A illustrates an implementation of a mechanism changer
interface coupled to a robotic arm in a robotic system, in
accordance with an embodiment of the present invention;
[0026] FIG. 5B illustrates an alternative view of male mechanism
changer interface 502 from FIG. 5A;
[0027] FIG. 5C illustrates a reciprocal female mechanism changer
interface coupled to an instrument device manipulator for
connecting with male mechanism changer interface 502 from FIGS. 5A
and 5B;
[0028] FIG. 5D illustrates an alternative view of female mechanism
changer interface 508 from FIG. 5C;
[0029] FIG. 6 illustrates a robotic surgery system that uses a
single port laparoscopic instrument connected through an instrument
interface on a single robotic arm that is directed at the abdomen
of a patient, in accordance with an embodiment of the present
invention;
[0030] FIG. 7 illustrates a robotic surgery system with two sets of
robotic subsystems, each with a pair of arms, in accordance with an
embodiment of the present invention;
[0031] FIG. 8A illustrates a robotic surgery system with a
subsystem with a single robotic arm, where a microscope tool is
connected to the robotic arm through an instrument interface, in
accordance with an embodiment of the present invention;
[0032] FIG. 8B illustrates a robotic surgery system where subsystem
801 from FIG. 8A may be used in conjunction with another subsystem
to perform microsurgery, in accordance with an embodiment of the
present invention;
[0033] FIG. 9A illustrates a portion of a robotic medical system
that includes a manipulator, in accordance with an embodiment of
the present invention;
[0034] FIG. 9B illustrates an alternative view of the robotic
medical system disclosed in FIG. 9A;
[0035] FIG. 10 illustrates an alternative view of the independent
drive mechanism from FIGS. 9A, 9B with a tension sensing apparatus
in accordance with an embodiment of the present invention;
[0036] FIG. 11A illustrates a cutaway view of the independent drive
mechanism from FIGS. 9A, 9B, and 10 from an alternate angle;
[0037] FIG. 11B illustrates a cutaway view of the previously
discussed independent drive mechanism in combination with an
endoscopic tool, in accordance with an embodiment of the present
invention;
[0038] FIG. 12 illustrates an alternative view of the
previously-discussed independent drive mechanism with pull wires
from an endoscopic tool in accordance with an embodiment of the
present invention;
[0039] FIG. 13 illustrates a conceptual diagram that shows how
horizontal forces may be measured by a strain gauge oriented
perpendicular to the forces, in accordance with an embodiment of
the invention;
[0040] FIG. 14 is an illustration of an endoscopic tool that may be
used in conjunction with a robotic system 100 from FIG. 1, in
accordance with an embodiment of the present invention;
[0041] FIGS. 15A, 15B, 15C, 16A, and 16B generally illustrate
aspects of a robotically-driven endoscopic tool, in accordance with
an embodiment of the present invention;
[0042] FIGS. 17A to 17D illustrates how prior art flexible
instruments exhibit undesirable "muscling" phenomenon when tendons
are pulled;
[0043] FIGS. 17E to 17H illustrate how prior art flexible
instruments suffer from curve alignment phenomenon during use in
non-linear pathways;
[0044] FIGS. 171 and 17J illustrate how the muscling and curve
alignment phenomena is substantially resolved through the provision
of a helixed section, in accordance with an embodiment of the
present invention;
[0045] FIG. 18 illustrates the structure of a flexible endoscopic
tool with an axially stiff tube within a lumen, in accordance with
an embodiment of the present invention;
[0046] FIG. 19 illustrates the structure of a helical pattern
within a lumen of a flexible endoscopic tool, in accordance with an
embodiment of the present invention;
[0047] FIG. 20A illustrates an endoscopic tool from a robotic
endolumenal system, in accordance with an embodiment of the present
invention;
[0048] FIG. 20B illustrates an alternative view of endoscopic tool
2000 from FIG. 20A;
[0049] FIG. 21 illustrates the distal end of an endoscopic tool, in
accordance with an embodiment of the present invention;
[0050] FIG. 22 illustrates a flowchart for a method of constructing
an endoscopic device with helical lumens, in accordance with an
embodiment of the present invention;
[0051] FIG. 23 illustrates a system for manufacturing a flexible
endoscope, in accordance with an embodiment of the present
invention;
[0052] FIG. 24 illustrates a specialized nose cone for
manufacturing an endoscopic device with helical pull lumens, in
accordance with an embodiment of the present invention;
[0053] FIGS. 25A and 25B illustrates the relationship between
centerline coordinates, diameter measurements and anatomical
spaces;
[0054] FIG. 26 illustrates a computer-generated three-dimensional
model representing an anatomical space, in accordance with an
embodiment of the invention;
[0055] FIG. 27 illustrates a robotic endolumenal system that makes
use of an electromagnetic tracker in combination with an
electromagnetic field generator, in accordance with an embodiment
in the present invention;
[0056] FIG. 28 illustrates a flow diagram for the steps for
registration, in accordance with an embodiment of the present
invention;
[0057] FIG. 29A illustrates the distal end of an endoscopic tool
within an anatomical lumen, in accordance with an embodiment of the
present invention;
[0058] FIG. 29B illustrates the endoscopic tool from FIG. 29A in
use at an operative site within an anatomical lumen, in accordance
with an embodiment of the present invention;
[0059] FIG. 29C illustrates the endoscopic tool from FIG. 29B in
use at an operative site within an anatomical lumen, in accordance
with an embodiment of the present invention;
[0060] FIG. 30A illustrates an endoscopic tool coupled to a distal
flexure section within an anatomical lumen, in accordance with an
embodiment of the present invention;
[0061] FIG. 30B illustrates an endoscopic tool from FIG. 30A with a
forceps tool in use at an operative site within an anatomical
lumen, in accordance with an embodiment of the present
invention;
[0062] FIG. 30C illustrates an endoscopic tool from FIG. 30A with a
laser device in use at an operative site within an anatomical
lumen, in accordance with an embodiment of the present invention;
and
[0063] FIG. 31 illustrates a command console for a robotic
endolumenal system, in accordance with an embodiment of the present
invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
[0064] Although certain preferred embodiments and examples are
disclosed below, inventive subject matter extends beyond the
specifically disclosed embodiments to other alternative embodiments
and/or uses, and to modifications and equivalents thereof. Thus,
the scope of the claims appended hereto is not limited by any of
the particular embodiments described below. For example, in any
method or process disclosed herein, the acts or operations of the
method or process may be performed in any suitable sequence and are
not necessarily limited to any particular disclosed sequence.
Various operations may be described as multiple discrete operations
in turn, in a manner that may be helpful in understanding certain
embodiments; however, the order of description should not be
construed to imply that these operations are order dependent.
Additionally, the structures, systems, and/or devices described
herein may be embodied as integrated components or as separate
components.
[0065] For purposes of comparing various embodiments, certain
aspects and advantages of these embodiments are described. Not
necessarily all such aspects or advantages are achieved by any
particular embodiment. Thus, for example, various embodiments may
be carried out in a manner that achieves or optimizes one advantage
or group of advantages as taught herein without necessarily
achieving other aspects or advantages as may also be taught or
suggested herein.
[0066] 1. Overview.
[0067] An endolumenal surgical robotic system provides the surgeon
with the ability to sit down in an ergonomic position and control a
robotic endoscopic tool to the desired anatomical location within a
patient without the need for awkward arm motions and positions.
[0068] The robotic endoscopic tool has the ability to navigate
lumens within the human body with ease by providing multiple
degrees of freedom at least two points along its length. The tool's
control points provide the surgeon with significantly more
instinctive control of the device as it navigates a tortuous path
within the human body. The tip of the tool is also capable of
articulation from zero to ninety degrees for all three hundred and
sixty degrees of roll angles.
[0069] The surgical robotic system may incorporate both external
sensor-based and internal vision-based navigation technologies in
order to assist the physician with guidance to the desired
anatomical location within the patient. The navigational
information may be conveyed in either two-dimensional display means
or three-dimensional display means.
[0070] 2. System Components.
[0071] FIG. 1 is a robotic endoscopic system, in accordance with an
embodiment of the present invention. As shown in FIG. 1, robotic
system 100 may comprises a system cart 101 with at least one
mechanical arm, such as arm 102. The system cart 101 may be in
communication with a remotely-located command console (not shown).
In practice, the system cart 101 may be arranged to provide access
to a patient, while a physician may control the system 100 from the
comfort of the command console. In some embodiments, the system
cart 100 may be integrated into the operating table or bed for
stability and access to the patient.
[0072] Within system 100, arm 102 may be fixedly coupled to a
system cart 101 that contains a variety of support systems,
including control electronics, power sources and optical sources in
some embodiments. The arm 102 may be formed from a plurality of
linkages 110 and joints 111 to enable access to the patient's
operative region. The system cart 103 may contain source of power
112, pneumatic pressure 113, and control and sensor electronics
114--including components such as central processing unit, data
bus, control circuitry, and memory--and related actuators or motors
that may drive arms such as arm 102. Power may be conveyed from the
system cart 101 to the arm 102 using a variety of means known to
one skilled in the art such as electrical wiring, gear heads, air
chambers. The electronics 114 in system cart 101 may also process
and transmit control signals communicated from a command
console.
[0073] The system cart 101 may also be mobile, as shown by the
wheels 115. In some embodiments, the system cart may capable of
being wheeled to the desired location near the patient. System
cart(s) 101 may be located in various locations in the operating
room in order to accommodate space needs and facilitate appropriate
placement and motion of modules and instruments with respect to a
patient. This capability enables the arms to be positioned in
locations where they do not interfere with the patient, doctor,
anesthesiologist or any supportive surgical equipment required for
the selected procedure. During procedures, the arms with
instruments will work collaboratively via user control through
separate control devices, which may include a command console with
haptic devices, joystick, or customized pendants.
[0074] 3. Mechanical Arms.
[0075] The proximal end of arm 102 may be fixedly mounted or
coupled to the cart 101. Mechanical arm 102 comprises a plurality
of linkages 110, connected by at least one joint per arm, such as
joints 111. If mechanical arm 102 is robotic, joints 111 may
comprise one or more actuators in order to affect movement in at
least one degree of freedom. The arm 102, as a whole, preferably
has more than three degrees of freedom. Through a combination of
wires and circuits, each arm may also convey both power and control
signals from system cart 101 to the instruments located at the end
of their extremities.
[0076] In some embodiments, the arms may be fixedly coupled to the
operating table with the patient. In some embodiments, the arms may
be coupled to the base of the operating table and reach around to
access patient.
[0077] In some embodiments, the mechanical arms may not be
robotically-driven. In those embodiments, the mechanical arms are
comprised of linkages and set up joints that use a combination of
brakes and counter-balances to hold the position of the arms in
place. In some embodiments, counter-balances may be constructed
from gas springs or coil springs. Brakes, such as fail safe brakes,
may be mechanical or electro-mechanical. In some embodiments, the
arms may be gravity-assisted passive support arms.
[0078] Distally, each arm may be coupled to a removable Instrument
Device Manipulator (IDM), such as 117, through a Mechanism Changer
Interface (MCI), such as 116. In the preferred embodiment, the MCI
116 may contain connectors to pass pneumatic pressure, electrical
power, electrical signals, and optical signals from the arm to the
IDM 117. In some embodiments, MCI 116 may be as simple as a set
screw or base plate connection.
[0079] IDM 117 may have a variety of means for manipulating a
surgical instrument including, direct drive, harmonic drive, geared
drives, belts and pulleys, or magnetic drives. One skilled in the
art would appreciate that a variety of methods may be used control
actuators on instrument devices.
[0080] Within the robotic system, the MCIs, such as 116, may be
interchangeable with a variety of procedure-specific IDMs, such as
117. In this embodiment, the interchangeability of the IDMs allow
robotic system 100 to perform different procedures.
[0081] Preferred embodiments may use a robotic arm with joint level
torque sensing having a wrist at the distal end, such as Kuka AG's
LBR5. These embodiments have a robotic arm with seven joints, with
redundant joints provided to avoid potential arm collision with a
patient, other robot arms, operating table, medical personal or
equipment proximate to the operative field, while maintaining the
wrist at the same pose so as not to interrupt an ongoing procedure.
The skilled artisan will appreciate that a robotic arm with at
least three degrees of freedom, and more preferably six or more
degrees of freedom, will fall within the inventive concepts
described herein, and further appreciate that more than one arm may
be provided with additional modules, where each arm may be commonly
or separately mounted on one or more carts.
[0082] 4. Virtual Rail Configuration.
[0083] Arm 102 in system 100 may be arranged in a variety of
postures for use in a variety of procedures. For example, in
combination with another robotic system, the arm 102 of system 100
may be arranged to align its IDM to form a "virtual rail" that
facilitates the insertion and manipulation of an endoscopic tool
118. For other procedures, the arms may be arranged differently.
Thus, the use of arms in system 100 provides flexibility not found
in robotic systems whose design is directly tied to specific
medical procedure. The arms of system 100 provides potentially much
greater stroke and stowage.
[0084] FIG. 2A illustrates a robotic surgery system 200 in
accordance with an embodiment of the present invention. System 200
has first arm 202 and second arm 204 holding endoscopic tool bases
206 and 208, respectively. Tool base 206 has controllable endoscope
sheath 210 operatively connected thereto. Tool base 208 has
flexible endoscope leader 212 operatively connected thereto.
[0085] Arms 202 and 204 align tool bases 206 and 208 such that
proximal end 216 of sheath 210 is distal of the proximal end 222 of
leader 212, and such that leader 212 remains axially aligned with
sheath 210 at an approximate angle of 180 degrees between the two
arms, resulting in a "virtual rail" where the rail is approximately
straight, or at 180 degrees. As will be described later, the
virtual rail may have angles between 90-180 degrees. In one
embodiment, sheath 210, with leader 212 slidingly disposed
therethrough, is robotically inserted through, for example, a
tracheal tube (not shown) in the mouth of and into patient 211, and
ultimately into the patient's bronchial system, while continually
maintaining the virtual rail during insertion and navigation. The
arms may move sheath 210 and endoscope 212 axially relative to each
other and in to or out of patient 211 under the control of a doctor
(not shown) at a control console 203 (from FIG. 2B).
[0086] Navigation is achieved, for example, by advancing sheath 210
along with leader 212 into the patient 211, then leader 212 may be
advanced beyond distal end 213 of the sheath, and the sheath 210
may then be brought even with the leader 212, until a desired
destination is reached. Other modes of navigation may be used, such
as and not by way of limitation using a guide wire through the
working channel of the leader 212. The physician may be using any
number of visual guidance modalities or combination thereof to aid
navigation and performing the medical procedure, e.g., fluoroscopy,
video, CT, MR etc. Distal end 220 of leader 212 may then be
navigated to an operative site and tools are deployed through a
longitudinally-aligned working channel within leader 212 to perform
desired procedures. The virtual rail may be maintained during the
navigation procedure and any subsequent operative procedures. Any
number of alternative procedures that may require a tool or no tool
at all can be performed using the flexible endoscope sliding
through the sheath, as the skilled artisan will appreciate.
[0087] FIG. 2B illustrates an overhead view of system 200 where
anesthesia cart 201 is provided towards the head of the patient.
Additionally, control console 203 with a user interface is provided
to control sheath 210, endoscope leader 212, and the associated
arms 202 and 204 and tool bases 206 and 208 (see FIG. 2A).
[0088] FIG. 2C shows an angled view of system 200 in FIG. 2A. Tool
modules 206 and 208 with associated sheath 210 and leader 212 are
attached to arms 202 and 204 and arranged in a 180 degree virtual
rail. The arms are shown on a single cart, which provides added
compactness and mobility. As will be discussed later, tool bases
206 and 208 have pulley systems or other actuation systems to
tension tendons in sheath 210 and leader 212 to steer their
respective distal ends. Tool bases 206 and 208 may provide other
desired utilities for the sheath and endoscope, such as pneumatic
pressure, electrical, data communication (e.g., for vision),
mechanical actuation (e.g., motor driven axels) and the like. These
utilities may be provided to the tool bases through the arms, from
a separate source or a combination of both.
[0089] FIGS. 2D and 2E illustrate alternative arrangements of arms
202 and 204 showing the versatility of the robotic surgical system
in accordance with embodiments of the present invention. In FIG.
2D, arms 202 and 204 may be extended to position the instrument
(comprising sheath 210 and leader 212) to enter the mouth of
patient 211 at 75 degrees from horizontal, while still maintaining
a 180 degree virtual rail. This may be done during the procedure if
required to accommodate space requirements within the room. The 75
degree angle was chosen for demonstrative purposes, not by way of
limitation.
[0090] FIG. 2E shows an alternative arrangement of arms 202 and 204
where the tool bases 206 and 208 are aligned to create a virtual
rail with a 90 degree angle, in accordance with an embodiment of
the present invention. In this embodiment, the instrument
(comprising sheath 210 and leader 212) enters the mouth of patient
213 at 75 degrees from horizontal. Tool bases 206 and 208 are
aligned such that the leader 212 bends 90 degrees at tool base 206
prior to entering the mouth of patient 213. To facilitate the bend
of leader 212, a rigid or semi-rigid structure, such as a tube, may
be used to ensure smooth extension and retraction of the leader 212
within sheath 210. Extension and retraction of leader 212 within
sheath 210 may be controlled by moving tool base 208 either closer
or farther from tool base 206 along the linear path tracked by
leader 212. Extension and retraction of sheath 210 may be
controlled by moving tool base 206 closer or farther from patient
213 along the linear path tracked by sheath 210. To avoid
unintended extension or retraction of leader 212 while extending or
retracting sheath 210, tool base 208 may also be moved along a
linear path parallel to sheath 210.
[0091] Virtual rails are useful in driving both rigid instrument
and flexible instruments, and especially where there are
telescoping requirements. The use of a virtual rail is not limited
to a single rail but can consist of multiple virtual rails where
the arms act in concert to maintain the individual virtual rails in
performance of one or more procedures.
[0092] FIG. 3A illustrates an overhead view of a system with
multiple virtual rails, in accordance with an embodiment of the
present invention. In FIG. 3A, robot arms 302, 304 and 306
respectively hold tool bases 308, 310, and 312. Tool bases 308 and
310 may be operatively coupled to flexible tool 314 and tool 316.
Tool 314 and tool 316 may be a telerobotically-controlled flexible
endoscopic instruments. Tool base 312 may be operatively coupled to
a dual lumen sheath 318, where each lumen receives tools 314 and
316. Arms 302 and 304 may each maintain a virtual rail with robotic
arm 306, and movements of all three arms may be coordinated to
maintain virtual rails and move tools 314, 316 and sheath 318
relative to each other and the patient.
[0093] FIG. 3B illustrates the use of the robotic surgery system
from FIG. 3A with an additional robotic arm 320 and associated tool
base 322 and tool 324. In this embodiment sheath 325 may have three
lumens. Alternatively, sheath 325 may comprise more than one sheath
to provide access to tools 314, 316, and 324. As will be
appreciated, the ability to increase or reduce the number of arms
with associated modules and instruments permits a great number and
flexibility of surgical configurations, which, in turn, permits
re-purposing of expensive arms and use of multiple
relatively-inexpensive modules to achieve great versatility at
reduced expense.
[0094] Thus, to create the virtual rail, a plurality of arms and/or
platforms may be utilized. Each platform/arm must be registered to
the others, which can be achieved by a plurality of modalities
including, vision, laser, mechanical, magnetic, or rigid
attachment. In one embodiment, registration may be achieved by a
multi-armed device with a single base using mechanical
registration. In mechanical registration, an embodiment may
register arm/platform placement, position, and orientation based on
their position, orientation and placement relative to the single
base. In another embodiment, registration may be achieved by a
system with multiple base using individual base registration and
"hand-shaking" between multiple robot arms. In embodiments with
multiple bases, registration may be achieved by touching together
arms from different bases, and calculating locations, orientation
and placement based on (i) the physical contact and (ii) the
relative locations of those bases. In some embodiments,
registration targets may be used to match the position and
orientations of the arms relative to each other. Through such
registration, the arms and instrument driving mechanisms may be
calculated in space relative to each other.
[0095] 5. Mechanism Changer Interface.
[0096] Returning to FIG. 1, robotic surgical system 100 may be
configured in a manner to provide a plurality of surgical system
configurations, such as by changing IDM 117 and tool 118 (also
known as an end effector). The system may comprise one or more
mobile robotic platforms staged at different locations in the
operative room, or at a convenient nearby location. Each platform
may provide some or all of power, pneumatic pressure, illumination
sources, data communication cables and control electronics for a
robotic arm that is coupled to the platform, and the module may
draw from these utilities as well. System 100 may alternatively
have multiple arms 102 mounted on one or more mobile carts 101, or
the arms may be mounted to the floor in order to provide a
plurality of surgical configurations.
[0097] In addition to multiple arms and platforms, some embodiments
are designed to readily exchange between multiple modules or end
effector mechanisms. Various surgical procedures or steps within a
procedure may require the use of different modules and the
associated instrument sets, for example, exchanging between
different sized sheath and endoscope combinations.
Interchangeability allows the system to reconfigure for different
clinical procedures or adjustments to surgical approaches.
[0098] FIG. 4 illustrates a robotic surgery system with
interchangeable IDMs and tools, in accordance with an embodiment of
the present invention. Surgical system 400 has a mechanical arm 401
to which IDM 402 and tool 403 are attached. Attached to system cart
404, IDMs 405 and 406, and associated tools 407 and 408 may be
exchanged onto robotic arm 401 or picked up by a different robotic
arm (not shown) to be used alone in concert with another IDM and
tool. Each IDM may be a dedicated electromechanical system which
may be used to drive various types of instruments and tools for
specified procedures. To drive instruments, each IDM may comprise
an independent drive system, which may include a motor. They may
contain sensors (e.g., RFID) or memory chips that record their
calibration and application related information. A system
calibration check may be required after a new mechanism is
connected to the robot arm. In some embodiments, an IDM may control
an endoscopic sheath or flexible endoscopic leader.
[0099] In FIG. 4, system 400 may exchange IDM 402 for IDMs 405 and
406 by itself through the use of global registration and sensors.
In some embodiments, IDMs 406 and 408 are stored on system cart 404
at predetermined "docking stations" which are configured with
identification and proximity sensors. Sensors at these stations may
make use of technologies such as RFID, optical scanners (e.g., bar
codes), EEPROMs, and physical proximity sensors to register and
identify which IDMs are "docked" at the docking station. As robotic
arm 401 and the IDM docking stations reside on system cart 404, the
identification and proximity sensors allow the IDMs that are
resting in the docking stations to be registered relative to the
robotic arm(s). Similarly, in embodiments with multiple arms on a
single system cart, multiple arms may access the IDMs on the
docking station using the combination of registration system and
sensors discussed above.
[0100] FIG. 5 illustrates a mechanism changer interface in a
robotic system, in accordance with an embodiment of the present
invention. FIG. 5A specifically illustrates an implementation of a
mechanism changer interface coupled to a robotic arm in a robotic
system, in accordance with an embodiment of the present invention.
As shown in FIG. 5A, the distal portion of robotic arm 500
comprises an articulating joint 501 coupled to a "male" mechanism
changer interface 502. Articulating joint 501 provides an
additional degree of freedom with respect to manipulating an
instrument device mechanism (not shown) that is configured to
couple to robotic arm 500. Male mechanism changer interface 502
provides a male connector interface 503 that provides a strong,
physical connection to the reciprocal female receptacle connector
interface on the IDM (not shown). The spherical indentations on the
male connector interface 503 physically couple to reciprocal
indentations on the female receptacle interface on the IDM. The
spherical indentations may be extended when pneumatic pressure is
conveyed along robotic arm 500 into male mechanism changer
interface 502. The male mechanism changer interface 502 also
provides connections 504 for transferring for pneumatic pressure to
the IDM. Additionally, this embodiment of the mechanism changer
interface provides for alignment sensors 505 that ensure that the
male mechanism changer interface 502 and its reciprocal female
interface are properly aligned.
[0101] FIG. 5B illustrates an alternative view of male mechanism
changer interface 502 separated from robotic arm 500. As discussed
with respect to FIG. 5A, male mechanism changer interface 502
provides for a flange-like male connector interface 503, pneumatic
connectors 504, and alignment sensors 505. Additionally, an
electrical interface 506 for connecting electrical signals to the
reciprocal interface on the IDM (not shown).
[0102] FIG. 5C illustrates a reciprocal female mechanism changer
interface coupled to an instrument device manipulator for
connecting with male mechanism changer interface 502 from FIGS. 5A
and 5B. As shown in FIG. 5C, instrument device manipulator 507 is
coupled to a female mechanism changer interface 508 that is
configured to connect to male mechanism changer interface 502 on
robotic arm 500. Female mechanism changer interface 508 provides
for female receptacle interface 509 that is designed to couple to
the flange-like male connector interface 503 of male mechanism
changer interface 502. The female receptacle interface 509 also
provides a groove to grip the spherical indentations on the male
connector interface 503. When pneumatic pressure is applied,
spherical indentations on male connector 503 are extended, and male
connector 503 and receptacle interfaces 509 securely couple the IDM
507 to the robotic arm 500. Reciprocal female mechanism changer
interface 508 also provides with pneumatic connectors 510 to accept
the pneumatic pressure conveyed from connectors 504.
[0103] FIG. 5D illustrates an alternative view of female mechanism
changer interface 508 from FIG. 5C. As discussed earlier,
reciprocal mechanism changer interface 508 contains a receptacle
interface 509, pneumatic connectors 510 for interfacing with
mechanism changer interface 502 on robotic arm 500. In addition,
mechanism changer interface 508 also provides for an electrical
module 511 for transmitting electrical signals--power, controls,
sensors--to module 506 in mechanism changer interface 502.
[0104] FIGS. 6, 7, 8A, and 8B illustrate interchangeable modules
that may be operated using system 400 from FIG. 4. FIG. 6
illustrates an embodiment of the present invention that uses a
single port laparoscopic instrument 601 connected through an
instrument interface 602 on a single robotic arm 603 that is
directed at the abdomen 604 of a patient 605.
[0105] FIG. 7 illustrates an embodiment of the present invention
with two sets of robotic subsystems 701 and 704, each with a pair
of arms 702, 703 and 705, 706 respectively. Connected through
instrument interfaces at the distal end of arms 702, 703, 705, 706
are laparoscopic instruments 707, 708, 709, 710 respectively, all
instruments working together to perform procedures in an individual
patient 711.
[0106] FIG. 8A illustrates an embodiment of the present invention
with a subsystem 801 with a single robotic arm 802, where a
microscope tool 804 connected to the robotic arm 802 through an
instrument interface 803. In some embodiments, the microscopic tool
804 may be used in conjunction with a second microscope tool 805
used by a physician 806 to aid in visualizing the operational area
of a patient 807.
[0107] FIG. 8B illustrates an embodiment of the present invention
where subsystem 801 from FIG. 8A may be used in conjunction with
subsystem 808 to perform microsurgery. Subsystem 808 provides arms
809 and 810, each with microsurgical tools 811 and 812 connected
through instrument interfaces on each respective arm. In some
embodiments, the one or more arms may pick up and exchange tools at
a table or other suitable holding mechanism within reach of the
robotic arm, such as a docking station.
[0108] In some embodiments, the mechanism changer interface may be
a simple screw to secure an associated IDM. In other embodiments,
the mechanism changer interface may be a bolt plate with an
electrical connector.
[0109] 6. Instrument Device Manipulator (IDM).
[0110] FIG. 9A illustrates a portion of a robotic medical system
that includes a manipulator, in accordance with an embodiment of
the present invention. System 900 includes a partial view of a
robotic arm 901, an articulating interface 902, an instrument
device manipulator ("IDM") 903, and an endoscopic tool 904. In some
embodiments, the robotic arm 901 may be only a linkage in a larger
robotic arm with multiple joints and linkages. The articulating
interface 902 couples IDM 903 to robotic arm 901. In addition to
coupling, the articulating interface 902 may also transfer
pneumatic pressure, power signals, control signals, and feedback
signals to and from the arm 901 and the IDM 903.
[0111] The IDM 903 drives and controls the endoscopic tool 904. In
some embodiments, the IDM 903 uses angular motion transmitted via
output shafts in order to control the endoscopic tool 904. As
discussed later, the IDM 903 may comprise a gear head, motor,
rotary encoder, power circuits, control circuits.
[0112] Endoscopic tool 904 may comprise a shaft 909 with a distal
tip and proximal end. A tool base 910 for receiving the control
signals and drive from IDM 903 may be coupled to the proximal end
of the shaft 909. Through the signals received by the tool base
910, the shaft 909 of endoscopic tool 904 may be controlled,
manipulated, and directed based on the angular motion transmitted
via output shafts 905, 906, 907, and 908 (see FIG. 9B) to the tool
base 910 of the endoscopic tool 904.
[0113] FIG. 9B illustrates an alternative view of the robotic
medical system disclosed in FIG. 9A. In FIG. 9B, the endoscopic
tool 904 has been removed from the IDM 903, to reveal the output
shafts 905, 906, 907, and 908. Additionally, removal of the outer
skin/shell of IDM 903 reveals the components below the IDM top
cover 911.
[0114] FIG. 10 illustrates an alternative view of the independent
drive mechanism from FIGS. 9A, 9B with a tension sensing apparatus
in accordance with an embodiment of the present invention. In
cutaway view 1000 of IDM 903, parallel drive units 1001, 1002,
1003, and 1004 are the structurally largest components in the IDM
903. In some embodiments, from the proximal to the distal end, a
drive unit 1001 may be comprised of a rotary encoder 1006, a motor
1005, and a gear head 1007. Drive units 1002, 1003, and 1004 may be
constructed similarly--comprising of motors, encoders, and gear
heads underneath the top cover 911. In some embodiments, the motor
used in the drive unit is a brushless motor. In other embodiments,
the motor may be a direct current servo motor.
[0115] Rotary encoder 1006 monitors and measures the angular speed
of the driveshaft of motor 1005. In some embodiments, rotary
encoder 1006 may be a redundant rotary encoder. The structure,
capabilities, and use of an appropriate redundant encoder is
disclosed in U.S. Provisional Patent Application No. 62/037,520,
filed Aug. 14, 2014, the entire contents of which are incorporated
by reference.
[0116] The torque generated by the motor 1005 may be transmitted to
gear head 1007 through a shaft coupled to the rotor of motor 1005.
In some embodiments, the gear head 1007 may be attached to the
motor 1005 in order to increase torque of the motor output, at the
cost of the rotational speed. The increased torque generated by
gear head 1007 may be transmitted into gear head shaft 1008.
Similarly, drive units 1002, 1003, and 1004 transmit their
respective torque out through gear head shafts 906, 907, and
908.
[0117] Each individual drive unit may be coupled to a motor mount
at its distal end and a strain gauge mount towards its proximal
end. For example, the distal end of drive unit 1001 may be clamped
to motor mount 1009 and strain gauge mount 1010. Similarly, drive
unit 1002 may be clamped to motor mount 1011, while also both being
clamped to strain gauge mount 1010. In some embodiments, the motor
mounts are constructed from aluminum to reduce weight. In some
embodiments, the strain gauge mounts may be adhered to a side of
the drive unit. In some embodiments, the strain gauge mounts may be
constructed from aluminum to reduce weight.
[0118] Electrical strain gauges 1012 and 1013 are potted and
soldered to the strain gauge mount 1010 and attached using screws
to motor mounts 1009 and 1011 respectively. Similarly, a pair of
strain gauges (not shown) proximal to drive units 1003 and 1004 are
potted and soldered to strain gauge mount 1014 and attached to
motor mounts 1015 and 1016 respectively using screws. In some
embodiments, the electrical strain gauges may be held in place to
their respective motor mount using side screws. For example, side
screws 1019 may be inserted into motor mount 1009 to hold in place
strain gauge 1012. In some embodiments, the gauge wiring in the
electrical strain gauges may be vertically arranged in order to
detect any vertical strain or flex in the drive unit which may be
measured as horizontal displacement by the motor mount (1009, 1011)
relative to the strain gauge mount (1010).
[0119] The strain gauge wiring may be routed to circuits on the
strain gauge mounts. For example, strain gauge 1012 may be routed
to circuit board 1017 which may be mounted on strain gauge mount
1010. Similarly, strain gauge 1013 may be routed to circuit board
1018 which may be also mounted on strain gauge mount 1010. In some
embodiments, circuit boards 1017 and 1018 may process or amplify
the signals from strain gauges 1012 and 1013 respectively. The
close proximity of circuit boards 1017 and 1018 to strain gauges
1012 and 1013 helps to reduce the signal to noise ratio in order to
obtain more accurate readings.
[0120] FIG. 11A illustrates a cutaway view of the independent drive
mechanism from FIGS. 9A, 9B, and 10 from an alternate angle. As
shown in FIG. 11A, a portion of outer shell/skin 1101 has been cut
away to reveal the innards of IDM 903. As discussed earlier, the
drive unit 1001 comprises of motor 1005, rotary encoder 1006, and
gear head 1007. The drive unit 1001 may be coupled to the motor
mount 1009 and passes through the top cover 911 through which the
output shaft 905 may be driven at the desired angular speed and
torque. The motor mount 1009 may be coupled to a vertically aligned
strain gauge 1012 using side screws. In addition to coupling to
motor mount 1009, the stain gauge 1012 may be potted into the
strain gauge mount 1010. In some embodiments, the output shaft 905
includes a labyrinth seal over a gear head shaft.
[0121] FIG. 11B illustrates a cutaway view of the previously
discussed independent drive mechanism in combination with an
endoscopic tool, in accordance with an embodiment of the present
invention. As shown in FIG. 11B, endoscopic tool 904, mounted on
IDM 903, contains pulleys that are longitudinally aligned with the
output shafts of the IDM 903, such as pulley 1102 which may be
concentric with output shaft 905. Pulley 1102 may be housed inside
of a precision cut chamber 1103 within tool base 910 such that the
pulley 1102 may be not rigidly fixed inside chamber 1103 but rather
"floats" within the space in the chamber 1103.
[0122] The splines of the pulley 1102 are designed such that they
align and lock with splines on output shaft 905. In some
embodiments, the splines are designed such that there may be only a
single orientation for the endoscopic tool to be aligned with IDM
903. While the splines ensure pulley 1102 is concentrically aligned
with output shaft 905, pulley 1102 may also incorporate use of a
magnet 1104 to position and axially hold the floating pulley 1102
in alignment with output shaft 905. Locked into alignment, rotation
of the output shaft 905 and pulley 1102 tensions the pull wires
within endoscopic tool 904, resulting in articulation of shaft
909.
[0123] FIG. 12 illustrates an alternative view of the
previously-discussed independent drive mechanism with pull wires
from an endoscopic tool in accordance with an embodiment of the
present invention. In some embodiments, the endoscopic tool may use
pull wires in order to articulate and control the shaft. In those
embodiments, these pull wires 1201, 1202, 1203, and 1204 may be
tensioned or loosened by the output shafts 905, 906, 907, and 908
respectively of the IDM 903. Accordingly, the pull wires may be
robotically controlled via the control circuity in IDM 903.
[0124] Just as the output shafts 905, 906, 907, and 908 transfer
force down pull wires 1201, 1202, 1203, and 1204 through angular
motion, the pull wires 1201, 1202, 1203, and 1204 transfer force
back to the output shafts and thus to the motor mounts and drive
units. For example, tension in the pull wires directed away from
the output shaft results in forces pulling the motor mounts 1009
and 1011. This force may be measured by the strain gauges, such as
1012 and 1013, since the strain gauges are both coupled to motor
mounts 1009 and 1011 and potted in the strain gauge mount 1010.
[0125] FIG. 13 illustrates a conceptual diagram that shows how
horizontal forces may be measured by a strain gauge oriented
perpendicular to the forces, in accordance with an embodiment of
the invention. As shown in diagram 1300, a force 1301 may directed
away from the output shaft 1302. As the output shaft 1302 is
coupled to the motor mount 1303, the force 1301 results in
horizontal displacement of the motor mount 1303. The strain gauge
1304, coupled to both the motor mount 1303 and ground 1305, may
thus experience strain as the motor mount 1303 causes the strain
gauge 1304 to flex (causing strain) in the direction of the force
1301. The amount of strain may be measured as a ratio of the
horizontal displacement of the tip of strain gauge 1304 to the
overall horizontal width of the strain gauge 1304. Accordingly, the
strain gauge 1304 may ultimately measure the force 1301 exerted on
the output shaft 1302.
[0126] In some embodiments, the assembly may incorporate a device
to measure the orientation of instrument device manipulator 903,
such as an inclinometer or accelerometer. In combination with the
strain gauges, measurements from the device may be used to
calibrate readings from the strain gauges, since strain gauges may
be sensitive to gravitational load effects resulting from their
orientation relative to ground. For example, if instrument device
manipulator 903 is oriented on its side, the weight of the drive
unit may create strain on the motor mount which may be transmitted
to the strain gauge, even though the strain may not result from
strain on the output shafts.
[0127] In some embodiments, the output signals from the strain
gauge circuit boards may be coupled to another circuit board for
processing control signals. In some embodiments, power signals are
routed to the drive units on another circuit board from that of
processing control signals.
[0128] As discussed earlier, the motors in drive units 1001, 1002,
1003, and 1004 ultimately drive output shafts, such as output
shafts 905, 906, 907, and 908. In some embodiments, the output
shafts may be augmented using a sterile barrier to prevent fluid
ingress into the instrument device manipulator 903. In some
embodiments, the barrier may make use of a labyrinth seal (1105
from FIG. 11A) around the output shafts to prevent fluid ingress.
In some embodiments, the distal end of the gear head shafts may be
covered with output shafts in order to transmit torque to a tool.
In some embodiments, the output shafts may be clad in a steel cap
to reduce magnetic conductance. In some embodiments, the output
shafts may be clamped to the gear head shafts to assist transfer of
torque.
[0129] Instrument device mechanism 903 may also be covered in a
shell or skin, such as outer shell/skin 1101. In addition to being
aesthetically pleasing, the shell provides fluid ingress protection
during operation, such as during medical procedures. In some
embodiments, the shell may be constructed using cast urethane for
electromagnetic shielding, electromagnetic compatibility, and
electrostatic discharge protection.
[0130] In an embodiment of the present invention, each of those
output shafts in individually tension may pull wires in an
endoscopic tool that makes use of steerable catheter technology.
Tensile force in the pull wires may be transmitted to the output
shafts 905, 906, 907 and 908 and down to a motor mount, such as
motor mounts 1009 and 1011.
[0131] 7. Endoscopic Tool Design.
[0132] In a preferred embodiment, robotic system 100 from FIG. 1
may drive a tool customized for endolumenal procedures, such as
endoscopic tool 118. FIG. 14 is an illustration of an endoscopic
tool that may be used in conjunction with a robotic system 100 from
FIG. 1, in accordance with an embodiment of the present invention.
Endoscopic tool 1400 may be arranged around nested
longitudinally-aligned tubular bodies, referred to as a "sheath"
and a "leader". The sheath 1401, the tubular tool with the larger
outer diameter, may be comprised of a proximal sheath section 1402,
a distal sheath section 1403, and a central sheath lumen (not
shown). Through signals received in the sheath base 1404, the
distal sheath portion 1403 may be articulated in the operator's
desired direction. Nested within the sheath 1401 may be a leader
1405 with a smaller outer diameter. The leader 1405 may comprise a
proximal leader section 1406 and a distal leader section 1407, and
a central working channel. Similar to sheath base 1404, leader base
1408 controls articulation of the distal leader section 1407 based
on control signals communicated to leader base 1408, often from the
IDMs (e.g., 903 from FIG. 9A).
[0133] Both the sheath base 1404 and leader base 1408 may have
similar drive mechanisms, to which control tendons within sheath
1401 and leader 1405 are anchored. For example, manipulation of the
sheath base 1404 may place tensile loads on tendons in the sheath
1401, therein causing deflection of distal sheath section 1403 in a
controlled manner. Similarly, manipulation of the leader base 1408
may place tensile loads on the tendons in leader 1405 to cause
deflection of distal leader section 1407. Both the sheath base 1404
and leader base 1408 may also contains couplings for the routing of
pneumatic pressure, electrical power, electrical signals or optical
signals from the IDMs to the sheath 1401 and leader 1404.
[0134] Control tendons within the sheath 1401 and leader 1405 may
be routed through the articulation section to an anchor positioned
distal to the articulation section. In a preferred embodiment, the
tendons within sheath 1401 and leader 1405 may consist of a
stainless steel control tendon routed through a stainless steel
coil, such as a coil pipe. One skilled in the arts would appreciate
that other materials may be used for the tendons, such as Kevlar,
Tungsten and Carbon Fiber. Placing loads on these tendons causes
the distal sections of sheath 1401 and leader 1405 to deflect in a
controllable manner. The inclusion of coil pipes along the length
of the tendons within the sheath 1401 and leader 1405 may transfer
the axial compression back to the origin of the load.
[0135] Using a plurality of tendons, the endoscopic tool 1400 has
the ability to navigate lumens within the human body with ease by
providing a plurality of degrees of freedom (each corresponding to
an individual tendon) control at two points--distal sheath section
1403 and distal leader section 1407--along its length. In some
embodiments, up to four tendons may be used in either the sheath
1401 and/or leader 1405, providing up to eight degrees of freedom
combined. In other embodiments, up to three tendons may be used,
providing up to six degrees of freedom.
[0136] In some embodiments, the sheath 1401 and leader 1405 may be
rolled 360 degrees, providing for even more tool flexibility. The
combination of roll angles, multiple degrees of articulation, and
multiple articulation points provides the surgeon with a
significant improvement to the instinctive control of the device as
it navigates a tortuous path within the human body.
[0137] FIGS. 15A, 15B, 15C, 16A, and 16B generally illustrate
aspects of a robotically-driven endoscopic tool, such a sheath 210
and leader 212 from FIG. 2, in accordance with an embodiment of the
present invention. FIG. 15A illustrates an endoscopic tool with
sheath 1500 having distal end 1501 and proximal end 1502 and lumen
1503 running between the two ends. Lumen 1503 may be sized to
slidingly receive a flexible endoscope (such as leader 1600 from
FIG. 16). Sheath 1500 has walls 1504 with tendons 1505 and 1506
running inside the length of walls 1504 of sheath 1500. Tendons
1505 and 1506 may slidingly pass through conduits 1507 and 1508 in
walls 1504 and terminate at distal end 1501. In some embodiments,
the tendons may be formed from steel. Appropriate tensioning of
tendon 1505 may compress distal end 1501 towards conduit 1507,
while minimizing bending of the helixed section 1510. Similarly,
appropriate tensioning of tendon 1506 may compress distal end 1501
towards conduit 1508. In some embodiments, lumen 1503 may not be
concentric with sheath 1500.
[0138] Tendons 1505 and 1506 and associated conduits 1507 and 1508
from sheath 1500 from FIG. 15A preferably do not run straight down
the entire length of sheath 1500, but helix around sheath 1500
along helixed section 1510 and then run longitudinally straight
(i.e., approximately parallel to the neutral axis) along distal
section 1509. It will be appreciated that helixed section 1510 may
begin from the proximal end of distal section 1509 extending
proximally down sheath 1510 and may terminate at any desired length
for any desired or variable pitch. The length and pitch of helixed
section 1510 may be determined based on the desired properties of
sheath 1500, taking into account desired flexibility of the shaft,
and increased friction in the helixed section 1510. Tendons 1505
and 1506 may run approximately parallel to central axis 1511 of
sheath 1500 when not in the helixed section, such as the proximal
and distal sections of the endoscope 1500.
[0139] In some embodiments, the tendon conduits may be at ninety
degrees to each other (e.g., 3-, 6-, 9- and 12-o'clock). In some
embodiments, the tendons may be spaced one hundred and twenty
degrees from each other, e.g., three total tendons. In some
embodiments, the tendons may be not be equally spaced. In some
embodiments, they may be to one side of the central lumen. In some
embodiments, the tendon count may differ from three or four.
[0140] FIG. 15B shows a three-dimensional illustration of an
embodiment of sheath 1500 with only one tendon for the purpose of
clarifying the distinction between non-helixed section 1509 and a
variable pitch helixed section 1510. While one tendon may be used,
it may be preferable to use multiple tendons. FIG. 15C shows a
three-dimensional illustration of an embodiment of sheath 1500 with
four tendons extending along distal section 1509, variable pitch
helixed section 1510.
[0141] FIG. 16A illustrates an endoscopic leader 1600 with distal
end 1601 and proximal end 1602, that may be sized to slidingly
reside within the sheath 1500 from FIG. 15. Leader 1600 may include
at least one working channel 1603 passing through it. Proximal end
1502 of sheath 1500 and proximal end 1602 of leader 1600 are,
respectively, operatively connected to tool bases 206 and 208 from
FIG. 2 respectively. Tendons 1604 and 1605 slidingly pass through
conduits 1606 and 1607 respectively in walls 1608 and terminate at
distal end 1601.
[0142] FIG. 16B illustrates the distal end 1601 of leader 1600, an
exemplary embodiment, that has imaging 1609 (e.g., CCD or CMOS
camera, terminal end of imaging fiber bundle etc.), light sources
1610 (e.g., LED, optic fiber etc.) and may include at least one
working channel opening 1603. Other channels or operating
electronics 1606 may be provided along leader 1600 to provide
various known capabilities at the distal end, such as wiring to
camera, insufflation, suction, electricity, fiber optics,
ultrasound transducer, EM sensing, and OCT sensing.
[0143] In some embodiments, the distal end 1601 of leader 1600 may
include a "pocket" for insertion of a tool, such as those disclosed
above. In some embodiments, the pocket may include an interface for
control over the tool. In some embodiments, a cable, such as an
electrical or optical cable, may be present in order communicate
with the interface.
[0144] In some embodiments, both sheath 1500 from FIG. 15A and
leader 1600 from FIG. 16A may have robotically-controlled steerable
distal ends. The structure of sheath 1500 and leader 1600 enabling
this control may be substantially the same. Thus, discussion for
the construction of sheath 1500 will be limited to that of the
sheath 1500 with the understanding that the same principles apply
to the structure of the leader 1600.
[0145] Therefore, tendons 1604 and 1605 and associated conduits
1606 and 1607 from the leader 1600 from FIG. 16A do not run
longitudinally straight (i.e., approximately parallel to the
neutral axis) down the length of leader 1600, but helix along
different portions of leader 1600. As with the helixed tendons and
conduits in sheath 1500, the helixed sections of leader 1600 may be
determined based on the desired properties of the leader, taking
into account desired flexibility of the shaft, and increased
friction in the helixed section. Tendons 1604 and 1605 run
approximately parallel to central axis of leader 1600 when not in
the helixed section.
[0146] The helixed section, as described more fully below, may help
isolate the bending to the distal section, while minimizing any
bending that occurs along the shaft proximal to the distal section.
In some embodiments of the present invention, the helix pitch of
the conduits in sheath 1500 and leader 1600 may be varied along the
length of the helixed section, which, as more fully described below
will alter the stiffness/rigidity of the shaft.
[0147] The use of helixed conduits and helixed tendons in sheath
1500 and leader 1600 present significant advantages over previous
flexible instruments without helixed conduits, particularly when
navigating non-linear pathways in anatomical structures. When
navigating curved pathways, it may be preferable for sheath 1500
and leader 1600 to remain flexible over most of the lengths
thereof, and to have a controllably steerable distal end section,
while also minimal secondary bending of the instrument proximal to
the distal bending section. In previous flexible instruments,
tensioning the tendons in order to articulate the distal end
resulted in unwanted bending and torqueing along the entire length
of the flexible instrument, which may be referred to as "muscling"
and "curve alignment" respectively.
[0148] FIGS. 17A to 17D illustrates how prior art flexible
instruments exhibit undesirable "muscling" phenomenon when tendons
are pulled. In FIG. 17A, a previous endoscope 1700 may have four
tendons or control wires along the length of the endoscope 1700
that run approximately parallel to the neutral axis 1701. Only
tendons 1702 and 1703 are shown in cross section traveling through
conduits 1704 and 1705 (also known as control lumens) in the shaft
wall, each of which are fixedly connected to a control ring 1706 on
the distal end of the endoscope 1700. Endoscope 1700 may be
intentionally designed to have a bending section 1707 and shaft
1708. In some flexible instruments, the shaft 1708 may incorporate
stiffer materials, such as stiffeners.
[0149] FIG. 17B illustrates an idealized articulation of bending
section 1707. By pulling or exerting tension on tendon 1703,
articulation of only the distal bending section 1707 results in an
amount represented by .phi., where the length difference at the
proximal ends of tendons 1702 and 1703 would be a f(.phi.). In
contrast, the shaft 1708 would remain straight along the neutral
axis 1701. This may be achieved by having a proximal region 1708 of
a significantly higher stiffness than the distal region of
1707.
[0150] FIG. 17C illustrates the real world result from tensioning
tendon 1703. As shown in FIG. 17C, pulling tendon 1703 results in
compressive forces along the entire length of the shaft as the
tension is non-localized. In an idealized situation, were tendon
1703 along the neutral axis 1701, the entire compressive load would
transmit equally down the central axis and most or all bending
would occur at the bending section 1707. However, where the tendon
1703 runs along the periphery of the shaft 1708, such as in
endoscope 1700, the axial load is transferred off the neutral axis
1701 in the same radial orientation of the neutral axis which
creates a cumulative moment along the neutral axis. This causes the
shaft 1708 to bend (depicted as .theta.), where the bend in the
shaft 1708 will be in the same direction as the bend in the bending
section 1707. The length along conduit 1704 and conduit 1705 must
change as the endoscope 1700 and distal bend section 1707 bend. The
amount tendons 1702 and 1703 extend from the proximal end is
f(.phi.,.theta.), as tendon 1703 will need to shorten and tendon
1702 will need to lengthen. This phenomenon, where the shaft 1707
and distal bending section 1708 bend from pulling tendon 1703, is
referred to as "muscling."
[0151] FIG. 17D illustrates the forces that contribute to muscling
in three-dimensions. As shown by FIG. 17D, tensioning tendon 1703
along endoscope 1700 causes the tendon 1703 to directionally exert
forces 1712 towards one side of the instrument. The direction of
forces 1712 reflect that the tension in tendon 1703 causes the
tendon to seek to follow a straight line from the tip of the distal
bending section 1707 to the base of the shaft 1708, i.e., the
lowest energy state as represented by the dotted line 1713. As will
be appreciated, if the shaft 1708 is rigid (i.e., not susceptible
to bending under the applicable forces), only the distal bending
section 1707 will bend. However, in many applications it is not
desirable to make the shaft rigidity sufficiently different from
the distal end to adequately minimize the muscling phenomenon.
[0152] FIGS. 17E to 17H illustrate how previous flexible
instruments suffer from curve alignment phenomenon during use in
non-linear pathways. FIG. 17E shows a previous flexible endoscope
1700 at rest within a non-linear path, represented by having a bend
.tau. along the shaft 1708 of endoscope 1700. For example, this may
result from the instrument navigating past a bend in the bronchial
lumens. Due to the non-linear bend, tendons 1702 and 1703 in
endoscope 1700 need to lengthen or shorten at the proximal end by a
length to accommodate the non-linear bend, which length is
represented by F(.tau.). Extension and compressive forces exist on
the lumens/conduits at the top and bottom of the bend, as depicted
by arrows 1709 (extension forces) and 1710 (compressive forces)
respectively. These forces exist because the distance along the top
of the bend is longer than the neutral axis, and the distance along
the inside of the bend is shorter than the neutral axis.
[0153] FIG. 17F illustrates the mechanics of articulating the
distal bending section 1707 of the endoscope 1700 in the same
direction as bend .tau., where one would pull tendon 1703. This
results in compressive forces along the length of the flexible
instrument (as previously described), and tendon 1703 also exerts
downward forces against the non-linear conduit through which it
passes, which applies an additive compression in the shaft 1708
previously compressed by the anatomical tortuosity. Since these
compressive leads are additive, the shaft 1708 will further bend in
the same direction as the distal bending section 1707. The
additional compressive force along the non-linear conduit may be
undesirable because: (i) it may unintentionally force the flexible
instrument against the anatomy; (ii) potential for injury distracts
the operator because he/she has to constantly monitor what the
shaft is doing, when he/she should be able to "assume" the anatomy
is governing the profile of the instrument shaft; (iii) it is an
inefficient way to bend the instrument, (iv) it is desired to
isolate bending at the distal section to aid in predictability and
controllability (i.e., ideal instrument will have bending section
that bends as commanded and is not a function of the anatomical
non-linear path), and (v) it forces a user to pull on a tendon 1103
an unpredictable additional length (.phi.+.theta.+.tau.).
[0154] FIG. 17G illustrates a scenario where one desires to
articulate the distal end opposite to bend .tau., requiring pulling
tendon 1702. Pulling tendon 1702 applies a compressive load 1711
along the top of the curve, which is in contrast to the extension
loads for the bend in its resting state as shown in FIG. 17E.
Tendons 1702 will attempt to return to its lowest energy state,
i.e., where the compressive load 1711 rests on the inside of the
bend .tau., and cause the shaft 1708 to rotate in the direction of
the arrow 1712 so that the tendon 1702 rests on the inside of the
bend .tau.. As shown in FIG. 17H, the rotation 1712 from tension on
tendon 1702 moves the compressive load 1711 to return to the inside
of the bend and causes the distal bending section 1707 to curl back
in the direction of bend .tau., resulting in articulation opposite
to that intended. The tension on tendon 1702, and the ensuing
rotation 1712, in practice returns endoscope 1700 to the same state
as in FIG. 17F. The phenomenon where the distal end articulation
curves back towards bend .tau. is known as "curve alignment." It
will be appreciated that curve alignment results from the same
forces that cause muscling, wherein those forces result in
undesirable lateral motion in the case of muscling and undesirable
rotational motion in the case of curve alignment. It is noted that
the discussions of the theory of muscling and curve alignment is
provided not by way of limitation, and embodiments of the present
invention are not in any way limited by this explanation.
[0155] FIGS. 17I and 17J illustrate how the muscling and curve
alignment phenomena is substantially resolved through the provision
of a helixed section in an embodiment of the present invention,
such as 1510 in FIG. 15. As shown in FIG. 17I, helixing the control
lumens around endoscope 1700, such as in helixed section 1510 from
FIG. 15, radially distributes compressive loads 1714 from a single
tendon 1715 around endoscope 1700. Because a tensioned tendon 1715
symmetrically transmits the compressive load 1714 in multiple
directions around the neutral axis, the bending moments imposed on
the shaft are also symmetrically distributed around the
longitudinal axis of the shaft, which counterbalance and offset
opposing compressive and tensile forces. The distribution of the
bending moments results in minimal net bending and rotational
forces, creating a lowest energy state that is longitudinally
parallel to the neutral axis, as represented by the dotted line
1816. This eliminates or substantially reduces the muscling and
curve alignment phenomena.
[0156] In some embodiments, the pitch of helixing can be varied to
affect friction and the stiffness of the helixed section. For
example, the helixed section 1510 may be shorter to allow for a
larger non-helixed section 1509, resulting in a larger articulating
section and possibly less friction.
[0157] Helical control lumens, however, create several trade-offs.
Helical control lumens still do not prevent buckling from tension
in the tendons. Additionally, while muscling is greatly reduced,
"spiraling"--the curving of the shaft into a spiral, spring-like
pattern due to tension in the tendons--is very common. Moreover,
helical control lumens requires compensation for additional
frictional forces as the tendon travels through the lumen for
longer distances.
[0158] FIG. 18 illustrates the structure of a flexible endoscopic
tool with an axially stiff tube within a lumen, in accordance with
an embodiment of the present invention. In FIG. 18, a section of an
endoscopic tool has a single lumen 1801 with a pull wire 1802
wrapped in a helical pattern around the shaft 1800. Inside the
lumen, an axially stiff tube 1803 "floats" around the pull wire
1802 and within the lumen 1801. Anchored at the beginning and end
of the helical portion of the shaft 1800, the floating tube 1803
extends and compresses in response to tension in pull wire 1802 and
external tortuosity, relieving the walls of lumen 1801 from the
extension and compression forces. In some embodiments, the tube
1803 may be anchored by control rings at the beginning and end of
the lumen. Alternatively, tube 1803 may be anchored using solder,
welding, gluing, bonding, or fusing methods to the beginning and
end of the lumen. In some embodiments, geometric engagement, such
as flared geometries, may be used to anchor tube 1803. In various
embodiments, the tube 1803 may be formed from hypodermic tubes,
coil pipes, Bowden cables, torque tubes, stainless steel tubes, or
nitinol tubes.
[0159] The embodiment in FIG. 18 may be constructed by fixedly
attaching the tubes to a distal end piece and proximal end piece
and collectively twisting the tubes by rotating either or both end
pieces. In this embodiment, the rotation of the end piece(s)
ensures that the tubes are helixed in the same pitch, manner, and
orientation. After rotation, the end pieces may be fixedly attached
to the lumen to prevent further rotation and restrict changes to
the pitch of the helixing.
[0160] FIG. 19 illustrates the structure of a helical pattern
within a lumen of a flexible endoscopic tool, in accordance with an
embodiment of the present invention. In FIG. 19, lumen 1900
contains structures 1901 and 1902 that form a helical or spiraled
pattern along its walls. In preferred embodiments, the structures
are formed from materials that are axially stiff and tube-like in
shape. In some embodiments, the structures may be formed from
hypodermic tubes ("hypo tube"), coil pipes, or torque tubes. As
shown by structures 1901 and 1902, the structures may have
different starting points along the walls of lumen 1900. The
materials, composition, and characteristics of structures 1901 and
1902 may also be selected and configured for desired stiffness and
length. The pitch of the helical pattern formed by structures 1901
and 1902 may also be configured for a desired stiffness and
flexibility of lumen 1900. In some embodiments, lumen 1900 may be
the main central lumen of a flexible endoscope, such as leader 1600
from FIG. 16.
[0161] FIG. 20A illustrates an endoscopic tool from a robotic
endolumenal system, in accordance with an embodiment of the present
invention. Endoscopic tool 2000 may comprise of a flexible shaft
section 2001 proximal to a support base (not shown) and a flexible
articulating section 2002 coupled to a distal tip 2003. Similar to
the leader 2005, endoscopic tool 2000 may be articulated by placing
tensile loads on tendons within the shaft.
[0162] FIG. 20B illustrates an alternative view of endoscopic tool
2000 from FIG. 20A. As shown in FIG. 20B, the distal tip 2003 may
comprise a working channel 2004, four light emitting diodes 2005,
and a digital camera 2006. In conjunction with the LEDs 2005, the
digital camera 2006 may be used, for example, to capture real-time
video to assist with navigation within anatomical lumens. In some
embodiments, the distal tip 2003 may comprise an integrated camera
assembly which houses a digital imaging means and illumination
means.
[0163] The working channel 2004 may be used for the passage of
intraoperative instruments, such as bending flexures for precise
articulation at an operative site. In other embodiments, working
channels may be incorporated to provide additional capabilities
such as flush, aspiration, illumination or laser energy. The
working channel may also facilitate the routing of control tendon
assemblies and other lumens needed for the aforementioned
additional capabilities. The working channel of the endoscopic tool
may also be configured to deliver a variety of other therapeutic
substances. Such substances may be cryogenic for ablation,
radiation, or stem cells. These substances may be precisely
delivered precisely to a target site using the insertion,
articulation, and capability of the endoscopic tool of the present
invention. In some embodiments, the working channel may be as small
at 1.2 millimeters in diameter.
[0164] In some embodiments, an electromagnetic (EM) tracker may be
incorporated into the distal tip 2003 in order to assist with
localization. As will be discussed later, in a static EM field
generator may be used to determine the location of the EM tracker,
and thus distal tip 2003 in real-time.
[0165] Images from camera 2006 may be ideal for navigating through
anatomical spaces. Thus, obscuring of the camera 2006 from internal
bodily fluids, such as mucus, may cause problems when navigating.
Accordingly, the distal end 2003 of endoscopic tool 2000 may also
include means for cleaning the camera 2006, such as means for
irrigation and aspiration of the camera lens. In some embodiments,
the working channel may contain a balloon that may be inflated with
fluid around the camera lens and aspirated once the lens was
clear.
[0166] The endoscopic tool 2000 enables the delivery and
manipulation of small instruments within the endolumenal space. In
a preferred embodiment, the distal tip may be miniaturized in order
to perform endolumenal procedures, maintaining an outer diameter of
no more than three millimeters (i.e., nine French).
[0167] FIG. 21 illustrates the distal end of an endoscopic tool, in
accordance with an embodiment of the present invention. As in FIG.
21A, endoscopic tool 2100 includes a distal end 2101 with an outer
casing 2102. Casing 2102 may be constructed from a number of
materials including stainless steel and polyether ether ketone
(PEEK). The distal end 2101 may be packed with a working channel
2103 for slidingly providing tool access and control. The distal
end 2101 may also provide for an array of light emitting diodes
2104 for illumination with use of the camera 2105. In some
embodiments, the camera may be part of a larger sensor assembly
that includes one or more computer processors, a printed circuit
board, and memory. In some embodiments, the sensor assembly may
also include other electronic sensors such as gyroscopes and
accelerometers (usage discussed later).
[0168] 8. Endoscopic Tool Manufacture.
[0169] In background, steerable catheters are traditionally
manufactured by braiding wires or fibers, i.e., braid wire, around
a process mandrel with pull lumens in a braiding machine, i.e.,
braider, and a polymer jacket applied over the braid wires.
Embodiments of the sheath and leader endoscopic tools may be
constructed using aspects of steerable catheter construction
methodologies.
[0170] FIG. 22 illustrates a flowchart for a method of constructing
an endoscopic device with helixed lumens, in accordance with an
embodiment of the present invention. To start, in step 2201, a main
process mandrel may be selected to create a cavity in the endoscope
for a central lumen that may be used a working channel.
Supplemental mandrels may be selected to create cavities in the
wall of the endoscope for use as control (pull) lumens. The main
process mandrel may exhibit larger outer diameters (OD) than the
supplemental mandrels to reflect the relative size differential
between a working channel and pull lumens. The supplemental
mandrels may be constructed a metal or thermoset polymer that may
or may not be coated with a lubricious coating, such as PTFE.
[0171] In step 2202, the main process mandrel may be inserted into
a feed tube of a braider that rotates relative to a fixed braid
cone support tube and braid cone holder. Similarly, the
supplemental mandrels may also be inserted into the feed tube in
parallel fashion to the main process mandrel. In traditional
endoscope construction, smaller supplemental mandrels are passed
through the center of the horn gears for braiding.
[0172] In step 2203, using a puller with a tread, the main process
mandrel may be advanced through the feed tube. As the main process
mandrel progresses, it eventually emerges through a center hole in
a nose cone. Similarly, the supplemental mandrels are advanced
through to also emerge through outer holes in the nose cone. This
contrasts with traditional endoscope construction, where
supplemental mandrels are typically advanced through separate feed
tubes to emerge from the center of the horn gears.
[0173] In step 2204, the main process mandrel and supplemental
mandrels are braided together using braid wire as they emerge
through the nose cone. The nose cone provides a round, smooth shape
on which the braid wire from the surrounding horn gears may easily
slide around the main process mandrel during the braiding process.
As both the main process mandrel and supplemental mandrels emerge
from the nose cone, the nose cone rotates, ensuring that the
supplemental mandrels in the outer holes are braided in a spiraled
fashion around the main process mandrel. As the main process
mandrel and supplemental mandrels are being braided together, the
horn gears translate and rotate to lay braid wire around both the
main process mandrel and supplemental mandrels at a pre-determined
pattern and density.
[0174] This method of braiding is significantly different from
traditional methods of endoscope construction, where the nose cone
is typically held in a position that is radially fixed relative to
the braid cone holder using a set screw keyed to the braid cone
holder. Thus, specialized hardware is required for the braiding
process in order to manufacture catheter-like endoscopes with
helical control lumens.
[0175] FIG. 23 illustrates a specialized system for manufacturing
an endoscope with helical pull lumens, in accordance with an
embodiment of the present invention. In system 2300, the nose cone
2301 may be fixedly coupled to a rotating feed tube 2302 using a
set screw that holds the nose cone 2301 in a fixed position
relative to the feed tube 2302. Thus, nose cone 2301 rotates as the
feed tube 2302 rotates. In contrast, traditional systems typically
use a set screw to fixedly couple the nose cone 2301 to the braid
cone support holder 2305, which does not rotate.
[0176] The center hole 2303 of the nose cone 2301 may be aligned
with the rotating feed tube 2302 in order to smoothly pull the main
process mandrel 2304 through both structures. In some embodiments,
the rotating feed tube 2302 has an outside diameter less than the
interior diameter of the braid cone support tube 2306, also known
as a mandrel guide tube, and an interior diameter larger than the
circumferential space of the center hole 2303 of the nose cone
2301. The rotating feed tube 2302 may generally be large enough for
the main process mandrel 2304 and the supplemental mandrels to be
passed through to the nose cone 2301 without entanglement. In some
embodiments, the rotating feed tube 2302 may be long enough to pass
through the center of the horn gears of the braider. In some
embodiments, the rotating feed tube 2302 may be attached to a
mechanism that may hold bobbins of material for the supplemental
mandrels that will be passed through the feed tube 2302 to
supplemental holes around the nose cone 2301.
[0177] In some embodiments, the feed tube 2302 may be attached to a
drive mechanism that controls the rate of rotation of the feed tube
2302 and thus the rotation of the nose cone 2301. In some
embodiments, the drive mechanism may be a rotating gear 2307. As
the braider is braiding the braid wires 2308 around the main
process mandrel 2304, the drive mechanism is either geared to the
braider itself or independently controlled to vary or hold constant
the rate of rotation of the rotating feed tube 2302 and thus the
rate of rotation of the nose cone 2301. The rate of rotation and
the rate of braiding will govern the pitch of the supplemental
mandrels on the main process mandrel 2304. As discussed earlier,
this may affect the flexibility, stiffness, and "pushability" of
the device.
[0178] FIG. 24 illustrates a specialized nose cone for
manufacturing helical lumens in an endoscopic device, in accordance
with an embodiment of the present invention. Rotating the nose cone
2400 at the same time that the main process mandrel 2401 is pulled
through the nose cone 2400 allows for supplemental mandrels 2402,
2403, and 2404 to be applied in a helical pattern around the
mandrel 2401 through supplemental holes 2405, 2406, and 2407
respectively that surround the center hole 2408, similar to how the
horn gears braid the braid wire around the main process mandrel
2401.
[0179] In another embodiment, varying the circumferential
orientation of the pull lumens may change the stiffness of the
helical section of the endoscope. In manufacture, this may be
achieved by altering the pitch of the supplemental, spiraling
mandrels. As the pitch (i.e., the angle off the longitudinal axis)
of the mandrels increases, the bending stiffness of the braided
composite decreases. Conversely, as the pitch of the supplemental
mandrels decreases, the bending stiffness increases. As shown in
FIG. 15B, in some embodiments, the pitch of the supplemental
mandrels may be varied within the helixed portion (1510). In those
embodiments, the bending stiffness of the braided composite may
vary even within the helixed portion.
[0180] Returning to FIG. 22, in step 2205, upon completion of the
braided process, a polymer coating or jacket may be sheathed,
heated, and bonded to the braiding composite. The polymer coating
may also be applied in an over-extrusion or a film-cast process. In
step 2206, after bonding, the mandrels may be removed from the
braided composite to create a central lumen or working channel
(main process mandrel) for camera and light tools, and several
control lumens (supplemental mandrels) for steering control. Having
removed the mandrels, the braided composite may be finished for
completion (2207).
[0181] During the braiding process, the braiding machine may be
stopped to make alterations to the braided composite. In some
embodiments, one alteration may be the addition of straight wires
or reinforcement rods. Reinforcement rods may significantly change
the buckling, axial and bending stiffness of a braided laminated
composite. Reinforcement rods may be particularly helpful for
longer endoscopes which may require specialized anti-buckling
construction or manual assistance to reduce the buckling of the
device so that it may be inserted into a patient. In some
embodiments, the braiding machine may be configured to selectively
braid reinforcement rods that may be pulled from holes in the nose
cone onto the main process mandrel, where the reinforcement rods
are captured and held in place by the braid wire. The absence of
reinforcement rods in the distal region of the resulting endoscope
preserves the device's flexibility in the distal end while
increasing the stiffness in the proximal region. This combination
of properties makes the resulting endoscope easier for a physician
to navigate, insert, and push the device into an endolumenal cavity
of a patient.
[0182] Applying supplemental mandrels onto a main process mandrel
using holes in a rotating nose cone provides a number of
manufacturing advantages. By using holes in the nose cone, the
mandrels are not pushed from the horn gears. Pushing mandrels from
the center of the individual horn gears, which are also responsible
for weaving the braid wire, results in the mandrels being
interwoven with the braid wire, which locks the resulting braid
matrix in place longitudinally. This form of construction, known as
"zero degree construction," limits the ability of the manufacturer
to adjust the braid matrix for desirable flexibility or hoop
strength. In zero degree construction, the supplemental mandrel is
necessarily confined in an "over-under manner" by the braid,
resulting in all clockwise braided braid wire being woven "over"
the supplemental mandrels, while all counter-clockwise braided
braid wire is woven "under" the supplemental mandrels. As zero
degree construction locks the supplemental mandrels in place
radially, it may be undesirable where varying the pitch of the
supplemental mandrel along the main process mandrel is
required.
[0183] Additionally, use of the horn gears as a pass-through for
the supplemental mandrels limits the number of supplemental
mandrels that may be applied to the main process mandrel. For
example, a sixteen carrier braider can apply up to eight mandrels,
a twenty-four carrier braider can only have up to twelve mandrels.
In contrast, use of holes in the nose cone allows any number of
mandrels to be passed through to the main process mandrel.
[0184] In some embodiments, the supplemental mandrels may be
applied to the main process mandrel without the benefit of a
second, outer layer of braid wire. Instead, the supplemental
mandrels may be applied without braid wire. In those embodiments,
the bonded/fused polymer jacket may hold the mandrels, and thus
lumens in place. Alternatively, in some embodiments, the mandrels
may be held in place using a casting around the braided composite.
Since the outer braid layer is absent from the manufacturing
endoscopic tool, the diameter and circumference of the device
cross-section is reduced. Alternatively, the supplemental mandrels
may be held in place by sleeving a polymer jacket over the main
process mandrel. In some embodiments, the casting may be the same
material as the exterior material for the endoscopic tool.
[0185] In some embodiments, the supplemental mandrels may be
braided onto the main process mandrel much like the braid wire. For
example, in some embodiments, the supplemental mandrels may be
braided using the even numbered horn gears, while held in place by
braid wire braided using the odd numbered horn gears. In this way,
the supplemental mandrels, and thus the lumens may be woven into
the walls of the central lumen. As an added benefit, embodiments
manufactured using this means also tend to have lower
circumferential area.
[0186] Alternatively, in some embodiments, the helixed lumen
structures may be manufactured using extruded molds. These molds
may generate the helixed lumen structures to create a jacket from
PTFE, pebax, polyurethane, and nylon. In some embodiments, the
extruded structures may be formed using a mold around a braided
mandrel.
[0187] In some embodiments, the helical lumen construction may be
performed by rotating the main process mandrel as it is being drawn
through the braider. By rotating the main process mandrel, instead
of the nose cone, the supplemental mandrels may be drawn through
either a fixed nose cone or through the center of the horn gears
during the braiding process. In this embodiment, the nose cone may
be fixedly coupled to the nose cone holder and the main process
mandrel is rotated as it drawn through the nose cone.
[0188] Construction of sheath 1500 from FIG. 15 and leader 1600
from FIG. 16 are substantially the same. Thus, one of skill in the
art would understanding that the same principles apply to both
tools.
[0189] 9. Endolumenal Navigation.
[0190] In an embodiment of the present invention, navigation of the
endoscopic tool through anatomical lumens may involve use of
computer-generated three-dimensional maps based on a collection of
two-dimensional images created by low dose computerized tomography
(CT) scans. Two-dimensional CT scans, each representing a cutaway
view of the patient's internal anatomy, may be collected during
pre-operative procedures. These scans may be analyzed to determine
cavities and anatomical spaces within the patient, such as branches
of a lung or the path of a urethra.
[0191] Having been analyzed to determine the relevant anatomical
spaces within the patient, the spaces may be expressed as lumens
with centerline coordinates, i.e., coordinates representing the
center of the lumen, in three-dimensional space. The volume of
those cavities may be represented as a specific measurement of
diameter distance at each centerline coordinate. By tracking the
centerline and the corresponding diameter distance measurements, a
computer-generated model of a three-dimensional lumen may be
generated. Grid coordinate data may thus be used to express
three-dimensional spaces and cavities that represent the patient's
anatomy.
[0192] FIG. 25 illustrates the relationship between centerline
coordinates, diameter measurements and anatomical spaces. In FIG.
25A, anatomical lumen 2500 may be roughly tracked longitudinally by
centerline coordinates 2501, 2502, 2503, 2504, 2505, and 2506 where
each centerline coordinate roughly approximates the center of the
lumen. By connecting those coordinates, as shown by "centerline"
2507, the lumen may be visualized. The volume of the lumen may be
further visualized by measuring the diameter of the lumen at each
centerline coordinate. Thus 2508, 2509, 2510, 2511, 2512, and 2513
represent the measurements of the lumen 2500 at coordinates 2501,
2502, 2503, 2504, 2505, and 2506.
[0193] In FIG. 25B, lumen 2500 may be visualized in
three-dimensional space by first locating the centerline
coordinates 2501, 2502, 2503, 2504, 2505, and 2506 in
three-dimensional space based on centerline 2507. At each
centerline coordinate, the lumen diameter may be visualized as a
two-dimensional circular space with diameters 2508, 2509, 2510,
2511, 2512, and 2513. By connecting those two-dimensional circular
spaces in three-dimensions, lumen 2500 may be approximated as
three-dimensional model 2514. More accurate approximations may be
determined by increasing the resolution of the centerline
coordinates and measurements, i.e., increasing the density of
centerline coordinates and measurements for a given lumen or
subsection. Centerline coordinates may also include markers to
indicate point of interest for the physician, including
lesions.
[0194] Having expressed, and subsequently generated, a
three-dimensional model of the anatomical space, a pre-operative
software package may also be used to analyze and derive an optimal
navigation path based on the generated module. For example, the
software package may derive shortest path to a single lesion
(marked by a centerline coordinate) or several lesions. This path
may be presented to the operator intra-operatively either in
two-dimensions or three-dimensions depending on the operator's
preference.
[0195] FIG. 26 illustrates a computer-generated three-dimensional
model representing an anatomical space, in accordance with an
embodiment of the invention. As discussed earlier, model 2600 may
be generated using centerline 2601 that was obtained by reviewing
CT scans that were performed preoperatively. In some embodiments,
computer software may be able to map the optimum path 2602 for the
endolumenal system to access an operative site 2603 within model
2600, and thus the corresponding anatomical space. In some
embodiments, the operative site 2603 may be linked to an individual
centerline coordinate 2604, which allows a computer algorithm to
topologically search the centerlines of model 2600 for the optimum
path 2602 for the endolumenal system.
[0196] Tracking the distal end of the endoscopic tool within the
patient's anatomy, and mapping that location to placement within a
computer model, enhances the navigational capabilities of the
endolumenal system. In order to track the distal working end of the
endoscopic tool, i.e., "localization" of the working end, a number
of approaches may be employed, either individually or in
combination.
[0197] In a sensor-based approach to localization, a sensor, such
as an electromagnetic (EM) tracker, may be coupled to the distal
working end of the endoscopic tool to provide a real-time
indication the progression of the endoscopic tool. In EM-based
tracking, an EM tracker, embedded in the endoscopic tool, measures
the variation in the electromagnetic field created by one or more
static EM transmitters. The transmitters (or field generators), may
be placed close to the patient to creates a low intensity magnetic
field. This induces small-currents in sensor coils in the EM
tracker, which are correlated to the distance and angle between the
sensor and the generator. The electrical signal may then be
digitized by an interface unit (on-chip or PCB) and sent via
cables/wiring back to the system cart and then to the command
module. The data may then be processed to interpret the current
data and calculate the precise location and orientation of the
sensor relative to the transmitters. Multiple sensors may be used
at different locations in the endoscopic device, for instance in
leader and sheath in order to calculate the individual positions of
those components. Thus, based on readings from an
artificially-generated EM field, the EM tracker may detect changes
in field strength as it moves through the patient's anatomy.
[0198] FIG. 27 illustrates a robotic endolumenal system that makes
use of an electromagnetic tracker in combination with an
electromagnetic field generator, in accordance with an embodiment
in the present invention. As robotic system 2700 drives a
robotically driven endoscopic tool 2701 into the patient 2702, an
electromagnetic (EM) tracker 2703 at the distal end of the
endoscopic tool 2701 may detect an EM field generated by EM field
generator 2704. The EM readings of the EM tracker 2703 may be
transmitted down the shaft of the endoscopic tool 2701 to the
system cart 2705 and to command module 2706 (which contains
relevant software modules, a central processing unit, a data bus
and memory) for interpretation and analysis. Using the readings
from EM tracker 2703, display modules 2707 may display the EM
tracker's relative position within a pre-generated
three-dimensional model for review by the operator 2708. The
embodiments also provide for the use of other types of sensors,
such as fiber optic shape sensors. While a variety of sensors may
be used for tracking, the choice of sensor may be inherently
limited based on (i) the size of the sensor within the endoscopic
tool and (ii) the cost of manufacturing and integration the sensor
into the endoscopic tool.
[0199] Prior to tracking a sensor through the patient's anatomy,
the tracking system may require a process known as "registration,"
where the system finds the geometric transformation that aligns a
single object between different coordinate systems. For instance, a
specific anatomical site on a patient has two different
representations in the CT model coordinates and in the EM sensor
coordinates. To be able to establish consistency and common
language between these coordinate systems, the system needs to find
the transformation that links these two representations, i.e.,
registration. In other words, the position of the EM tracker
relative to the position of the EM field generator may be mapped to
a three-dimensional coordinate system to isolate a location in a
corresponding three-dimensional model.
[0200] In some embodiments, registration may be performed in
several steps. FIG. 28 illustrates a flow diagram for a
registration process, in accordance with an embodiment of the
present invention. To start, in step 2801, the operator must first
position the working end of the endoscopic tool at a known starting
location. This may involve using video imagery data from the
endoscopic camera to confirm the starting location. Initial
positioning may be accomplished by identifying anatomical features
through a camera located at the working end of the endoscope. For
example, in bronchoscopy, registration may be performed by locating
the base of the trachea, distinguished by locating the two main
bronchial tubes for the left and right lung. This location may be
ascertained using video images received by the camera in the distal
end of the endoscopic. In some embodiments, the video data may be
compared to different cross sectional views of a pre-generated
computer model of the patient's anatomy. By sorting through
cross-sectional views, the system may identify the location
associated with the cross-section with the smallest amount of
differences, or "errors," to find the "match."
[0201] In step 2802, the operator may "drive" or "extend" the
endoscopic tool into unique anatomical spaces that have already
been mapped. For example, in bronchoscopy, the operator may drive
the endoscope down unique bronchial paths from the base of the
trachea. Because the base of the trachea splits into two bronchial
tubes, an operator may drive the endoscopic tool into one tube and
track the working end of the endoscopic tool using an EM
tracker.
[0202] In step 2803, the operator monitors the relative travel of
the endoscopic tool. Monitoring of the endoscopic tool may make use
of either the EM tracker or fluoroscopy to determine relative
movement of the endoscopic tool. Evaluation of the relative
displacement of the working end of the endoscopic tool may be
compared the computer model generated from pre-operative CT scan
data. In some embodiments, the relative movement may be matched
with centerlines in the computer model, where the transformation
matrix leads to the least error is the correct registration. In
some embodiments, the system and operator may track insertion data
(discussed below) and orientation data from an accelerometer and/or
gyroscope (discussed below).
[0203] In step 2804, the operator may decide to drive into more
anatomical spaces (2802) and collect more locational information
(2803) prior to comparing and analyzing the positional data. For
example, in bronchoscopy, the operator retract the endoscope from
one bronchial tube back the tracheal tube and drive the endoscope
into another bronchial tube in order to collect more positional
data. Once the operator is satisfied, the operator may stop driving
(2802) and monitoring positional data (2803) and proceed to process
the data.
[0204] In step 2805, the system may analyze the collected
positional data and compare the data to pre-generated computer
models to register the displacement of the endoscope within
patient's anatomy to the model. Therefore, by comparing the
movement in the patient's anatomy to the three-dimensional model of
the patient's anatomy, the system may be able to register the
tracker relative to both spaces--three-dimensional computer model
vs. patient anatomical space. After analysis, the registration
process may be complete (2806).
[0205] In some cases, it may be necessary to perform a "roll
registration" in order to confirm the orientation of the endoscopic
tool. This may be particularly important in step 2801 prior to
driving into un-registered anatomical spaces. In bronchoscopy,
proper vertical orientation ensures that the operator may
distinguish between the right and left bronchi. For example within
the base of the trachea, images of the left and right bronchi may
appear very similar regardless of whether the camera is oriented at
zero degrees or one-hundred eighty degrees. Roll registration may
also be important because the kinematics of the endoscopic tool
typically results in a slight rotation during tortuous navigation
within a patient.
[0206] Roll registration may be important at the operative site
when the working channel may be occupied by the sensor. For
example, in embodiments with only a single working channel, upon
reaching the operative site, the physician may need to remove the
EM tracker from the endoscopic tool in order to make use of another
tool, such as a grasper or forceps. Upon removal, however, the
system may lose its localization capabilities without the EM
tracker. Thus, when ready to leave the operative region, insertion
of the EM tracker may require that the roll registration be again
performed to ensure proper orientation.
[0207] In some embodiments, the rotation of the endoscopic tool may
be tracked using an accelerometer mounted within the distal working
end of the device. Use of an accelerometer to detect gravitational
forces on the endoscope provides information regarding the location
of the endoscopic tool relative to the ground. The location of the
ground relative to the endoscope may be used to solve certain
ambiguities. In bronchoscopy, for example, knowing the orientation
(0 or 180 degrees) of the distal camera of the endoscope would help
determine the appropriate bronchial branch at the start. During
navigation, data from the accelerometer to track the direction of
gravity, and thus orientation, may also be used to auto-correct the
camera image displayed on the control console, ensuring that the
displayed image is always oriented vertically.
[0208] In a preferred embodiment, a 3-axis MEMS-based sensor chip
with an accelerometer may be coupled near the tip of the endoscopic
device, on the same printed circuit board as the digital camera.
The accelerometer measures the linear acceleration along the three
different axes to calculate the velocity and direction of the
catheter tip. It accelerometer also measures the direction of
gravity and thus provides absolute information about the
orientation of the endoscopic device. The accelerometer readings re
be transmitted using digital or analog signals through a
communication protocol like I2C. The signal may be transmitted
through wiring to the proximal end of the catheter and from there
to the system cart and command module for processing.
[0209] In a three-axis sensor, the accelerometer may be able to
determine location of the ground relative to the endoscope. If the
endoscope does not roll or bend up to ninety degrees, a two axis
accelerometer could be also be useful. Alternatively, a one-axis
sensor may be useful if the axis of the accelerometer remains
perpendicular to the direction of gravity, i.e., perpendicular to
the ground. Alternatively, a gyroscope may be used to measure the
rate of rotation, which may then be used to calculate the
articulation of the endoscopic device.
[0210] Some embodiments make use of an EM tracker in combination
with the accelerometer to supplement any orientation readings from
the accelerometer. In some embodiments, use of fluorescopy to track
the endoscopic tool may also supplement the registration process.
As known in the art, fluoroscopy is an imaging technique that uses
X-rays to obtain real-time moving images of the internal structures
of a patient through the use of a fluoroscope. Two-dimensional
scans generated by fluoroscopy may assist with localization in
certain situations, e.g., identifying the relevant bronchi.
[0211] Tracking using fluorescopy may be performed using a
plurality of radio-opaque markers on the endoscope. Many features
of the endoscope are naturally radio-opaque to x-rays, including
the camera head, the control ring and pull wires; thus, the marker
location together with the metallic components of the endoscope may
be used to obtain a three-dimensional transformation matrix. Once
registration has happened, visual images detecting branch locations
may be precisely correlated to the three-dimensional model. In
addition, the full branch length and branch location in 3D can be
measured and enhanced in the map.
[0212] In contrast to a sensor-based approach, vision-based
tracking involves using images generated by a distally-mounted
camera to determine the location of the endoscopic tool. For
example, in bronchoscopy, feature tracking algorithms may be used
to identify circular geometries corresponding to bronchial paths
and track the change of those geometries from image to image. By
tracking the direction of those features as they move from image to
image, the system may be able to determine which branch was
selected, as well as the relative rotational and translational
motion of the camera. Use of a topological map of the bronchial
paths may further enhance vision-based algorithms.
[0213] In addition to feature based tracking, image processing
techniques such as optical flow may also be used to identify
branches in the airway topology in bronchoscopy. Optical flow is
the displacement of image pixels from one image to the next in a
video sequence. With respect to bronchoscopy, optical flow may be
used to estimate the movement of the tip of the scope based on
changes in the camera images received at the tip of the scope.
Specifically, in a series of video frames, each frame may be
analyzed to detect translation of the pixels from one frame to the
next. For example, if the pixels in a given frame appear to
translate to the left in the next frame, the algorithm would infer
that the camera, and in turn the tip of the scope, moved to the
right. Through comparing many frames over many iterations, movement
(and thus location) of the scope may be determined.
[0214] Where stereoscopic image capture--as opposed to monocular
image capture--is available, optical flow techniques may also be
used to complement the pre-existing three-dimensional model of the
anatomic region. Using stereoscopic image capture, the depth of the
pixels in the two-dimensional captured images may be determined to
build a three-dimensional map of objects in the camera view.
Extrapolating to travel within an anatomical lumen, this technique
enables the system to develop three-dimensional maps of the local
surroundings around the endoscope while navigating in inside the
patient's anatomy. These maps may be used to extend the
pre-determined three-dimensional computer models where the models
either are missing data or of low quality. In addition to a
stereoscopic camera apparatus, depth sensors or specific lighting
configurations and image capture techniques--such as RGB-D sensors
or structure lighting--may need to be used.
[0215] Regardless of tracking method--either sensor-based or
vision-based--tracking may be improved by using data from the
endoscopic tool itself. For example, in endoscopic tool 200 from
FIG. 2, the relative insertion length of sheath 201 and leader 205
may be measured from a known, starting position within the trachea
(in the case of bronchoscopy). Using relative insertion length and
the centerlines of a three-dimensional model of the patient's
bronchial tree, the system may giving a rough estimation of the
location of the working end after determining whether the
endoscopic tool is located in a branch and the distance traveled
down that branch. Other control information from the endoscopic
tool may also be used, such as endoscope device articulation, roll,
or pitch and yaw.
[0216] Real-time imaging based on different imaging modalities
would further enhance navigation, particularly at the operative
site. Even though tracking may assist with rough navigation to the
operative site, additional modalities may be useful when more
precise handling is necessary, such when attempting to biopsy a
lesion. Imaging tools such as fluorescence imaging, near infrared
imaging, oxygen sensors, molecular biomarker images, and contrast
dye imaging may help pinpoint the exact coordinates of the lesion
in the computer model, and thus assist with operating a biopsy
needle at the operative site. In the absence of a precise location,
the endoscopic tool may be used to biopsy the entire region of the
operative site at a known depth, thus ensuring tissue from the
lesion is sampled.
[0217] In some cases, the segmented CT scans, and thus the
resulting computer models, do not show branches at the periphery of
the lung (in the context of bronchoscopy). This may be due to
insufficient inflation of the airways during a scan, or because the
size of the branches is below the resolution of a CT scan
(typically on the order of 1 millimeter). In practice, the robotic
system may enhance the computer model during the procedure by
noting the location and the position and orientation of the
unmapped branch. In some embodiments, the topology structure may
allow physicians to mark their location and return to that same
location in order to examine the periphery branches. In some
embodiments, the endoscopic camera may measure the diameter and
shape of the branches based on the capture images, allowing those
branches to be mapped based on position and orientation.
[0218] 10. Endolumenal Procedures.
[0219] FIG. 29A illustrates the distal end of an endoscopic tool
within an anatomical lumen, in accordance with an embodiment of the
present invention. In FIG. 29A, endoscopic tool 2900, comprising a
shaft 2901 is shown navigating through an anatomical lumen 2902
towards an operative site 2903. During navigation, the shaft 2901
may be unarticulated.
[0220] FIG. 29B illustrates the endoscopic tool from FIG. 29A in
use at an operative site within an anatomical lumen. Having reached
the operative site 2903, a distal leader section 2904,
longitudinally aligned with the shaft 2901, may be extended from
shaft 2901 in the direction marked by arrow 2905. Distal leader
section 2904 may also be articulated in order to direct tools
towards operative site 2903.
[0221] FIG. 29C illustrates the endoscopic tool from FIG. 29B in
use at an operative site within an anatomical lumen. In cases where
the operative site contains a lesion for biopsy, the distal leader
section 2904 may articulate in the direction marked by arrow 2906
to convey an aspiration needle 2907 to target a lesion at operative
site 2903. In some embodiments, distal leader section 2904 may be
articulated to direct biopsy forceps to remove samples of
anatomical tissues for purposes of intraoperative evaluation. For
purposes of activation of that end effector, endoscopic tool 2900
may comprise a tendon operatively coupled to the biopsy
forceps.
[0222] FIG. 30A illustrates an endoscopic tool coupled to a distal
flexure section within an anatomical lumen, in accordance with an
embodiment of the present invention. In FIG. 30A, an endoscopic
tool 3000, comprising a shaft 3001, flexure section 3002, and
forceps 3003, is shown navigating through an anatomical lumen 3004
towards an operative site. During navigation, both the shaft 3001
and distal flexure section 3002 may be unarticulated as shown in
FIG. 30A. In some embodiments, the flexure section 3002 may be
retracted within shaft 3001. The construction, composition,
capabilities, and use of flexure section 3002 is disclosed in U.S.
patent application Ser. No. 14/201,610, filed Mar. 7, 2014, and
U.S. patent application Ser. No. 14/479,095, filed Sep. 5, 2014,
the entire contents of which are incorporated by reference.
[0223] In some embodiments, the flexure 3002 may be
longitudinally-aligned with the shaft 3001. In some embodiments,
the flexure 3002 may be deployed through a working channel that is
off-axis (neutral axis) of shaft 3001, allowing for the flexure
3002 to operate without obscuring a camera located at the distal
end of shaft 3001. This arrangement allows an operator to use a
camera to articulate flexure 3002 while shaft 3001 remains
stationary.
[0224] Similar to other embodiments, different tools, such as
forceps 3003, may be deployed through the working channel in
flexure section 3002 for use at the distal end of the flexure
section 3002. In other scenarios, surgical tools such as graspers,
scalpels, needles, and probes may be located at the distal end of
the flexure section 3002. In endoscopic tool 3000, as in other
embodiments, the tool at the distal end of the bending section may
be substituted intra-operatively in order to perform multiple
treatments in a single procedure.
[0225] FIG. 30B illustrates an endoscopic tool from FIG. 30A with a
forceps tool in use at an operative site within an anatomical
lumen, in accordance with an embodiment of the present invention.
Navigation of endoscopic tool 3000 through anatomical lumen 3004
may be guided by any number of the various navigational
technologies discussed above. Once the endoscopic tool 3000 has
reached its desired location at the operative site 3006, flexure
section 3002 may articulate in the direction of arrow 3005 in order
to orient forceps 3003 towards operative site 3006. Using forceps
3003, endoscopic tool 3000 may take a biopsy of the tissue at the
operative site 3006.
[0226] FIG. 30C illustrates an endoscopic tool from FIG. 30A with a
laser device in use at an operative site within an anatomical
lumen, in accordance with an embodiment of the present invention.
Having reached the operative site 3006, the flexure section 3002 of
endoscopic tool 3000 may be articulated and a laser tool 3007 may
be deployed through the working channel of the shaft 3001 and
flexure section 3002. Once deployed, the laser tool 3007 may be
directed to operative site 3006 to emit laser radiation 3008 for
purposes of tissue ablation, drilling, cutting, piercing,
debriding, cutting or accessing non-superficial tissue.
[0227] 11. Command Console.
[0228] As discussed with respect to system 100 from FIG. 1, an
embodiment of the command console allows an operator, i.e.,
physician, to remotely control the robotic endolumenal system from
an ergonomic position. In the preferred embodiment, the command
console utilizes a user interface that both (i) enables the
operator to control the robotic endoscopic tool, and (ii) displays
the navigational environment from an ergonomic position.
[0229] FIG. 31 illustrates a command console for a robotic
endolumenal system, in accordance with an embodiment of the present
invention. As shown in FIG. 31, command console 3100 may comprise a
base 3101, display modules, such as monitors 3102, and control
modules, such as keyboard 3103 and joystick 3104. In some
embodiments, the command module functionality may be integrated
into the system cart with the mechanical arms, such as system cart
101 from system 100 in FIG. 1.
[0230] The base 3101 may comprise of a central processing unit, a
memory unit, a data bus, and associated data communication ports
that are responsible for interpreting and processing signals, such
as camera imagery and tracking sensor data, from the endoscopic
tool. In other embodiments, the burden of interpretation and
processing signals may be distributed between the associated system
cart and the command console 3100. The base 3101 may also be
responsible for interpreting and processing commands and
instructions from the operator 3105 through the control modules,
such as 3103 and 3104.
[0231] The control modules are responsible for capturing the
commands of the operator 3105. In addition to the keyboard 3103 and
joystick 3104 in FIG. 31, the control modules may comprise other
control mechanisms known in the art, including but not limited to
computer mice, trackpads, trackballs, control pads, and video game
controllers. In some embodiments, hand gestures and finger gestures
may also be captured to deliver control signals to the system.
[0232] In some embodiments, there may be a variety of control
means. For example, control over the endoscopic tool may be
performed in either a "Velocity mode" or "Position control mode".
"Velocity mode" consists of directly controlling pitch and yaw
behaviors of the distal end of the endoscopic tool based on direct
manual control, such as through joystick 3104. For example, right
and left motions on joystick 3104 may be mapped to yaw and pitch
movement in the distal end of the endoscopic tool. Haptic feedback
in the joystick may also be used to enhance control in "velocity
mode". For example, vibration may be sent back to the joystick 3104
to communicate that the endoscopic tool cannot further articulate
or roll in a certain direction. Alternatively, pop-up messages
and/or audio feedback (e.g., beeping) may also be used to
communicate that the endoscopic tool has reached maximum
articulation or roll.
[0233] "Position control mode" consists of identifying a location
in a three-dimensional map of the patient and relying on the
robotic system to robotically steer the endoscopic tool the
identified location based on pre-determined computer models. Due to
its reliance on a three-dimensional mapping of the patient,
position control mode requires accurate mapping of the patient's
anatomy.
[0234] Without using the command module 3101, the system may also
be directly manipulated by manual operators. For example, during
system setup, physicians and assistants may move the mechanical
arms and endoscopic tools to arrange the equipment around the
patient and the operating room. During direct manipulation, the
system may rely on force feedback and inertia control from human
operators to determine the appropriate equipment orientation.
[0235] The display modules 3102 may comprise monitors, virtual
reality viewing devices, such as goggles or glasses, or other means
of display visual information regarding the system and from the
camera in the endoscopic tool (if any). In some embodiments, the
control modules and display modules may be combined, such as in a
touchscreen in a tablet or computer device. In a combined module,
the operator 3105 may be able to view visual data as well as input
commands to the robotic system.
[0236] In another embodiment, display modules may display
three-dimensional images using a stereoscopic device, such as a
visor or goggle arrangement. Using three-dimensions images, the
operator may view an "endo view" of the computer model, a virtual
environment of the interior of the three-dimensional
computer-generated model of the patient's anatomy to approximate
the expected location of the device within the patient. By
comparing the "endo view" to the actual camera images, the
physician may be able to mentally orient himself and confirm that
the endoscopic tool is in the right location within the patient.
This may give the operator a better sense of the anatomical
structures around the distal end of the endoscopic tool.
[0237] In a preferred embodiment, the display modules 3102 may
simultaneously display the pre-generated three-dimensional models,
the pre-determined optimal navigation paths through the models, and
CT scans of the anatomy at the current location of the distal end
of the endoscopic tool. In some embodiments, a model of the
endoscopic tool may be displayed with the three-dimensional model
of the patient's anatomy, to further clarify the status of the
procedure. For example, a lesion may have been identified in a CT
scan where a biopsy may be necessary.
[0238] During operation, camera means and illumination means at the
distal end of the endoscopic tool may generate a reference image in
the display modules for the operator. Thus, directions in the
joystick 3104 causing articulation and rolling of the distal end of
the endoscopic tool results in an image of the anatomical features
directly in front of the distal end. Pointing the joystick 3104 up
may raise the pitch of the distal end of the endoscopic tool with
the camera, while pointing the joystick 3104 down may decrease the
pitch.
[0239] The display modules 3102 may automatically display different
views of the endoscopic tool depending on the operators' settings
and the particular procedure. For example, if desired, an overhead
fluoroscopic view of the endolumenal device may be displayed during
the final navigation step as it approached the operative
region.
[0240] Elements or components shown with any embodiment herein are
exemplary for the specific embodiment and may be used on or in
combination with other embodiments disclosed herein. While the
invention is susceptible to various modifications and alternative
forms, specific examples thereof have been shown in the drawings
and are herein described in detail. The invention is not limited,
however, to the particular forms or methods disclosed, but to the
contrary, covers all modifications, equivalents and alternatives
thereof.
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